ll  I 


-. 


THE 

MOTORMAN 

AND    HIS   DUTIES 


A  Handbook  of  Theory  and  Practice  for 
Operating  Electric  Cars 


BY 

LUDWIG  GUTMANN 


CONSUL 


FIFTH  EDITION  REVISED  AND  ENLARGED 

BY 
GEORGE  RICHMOND  METCALFE.   M.  E. 


CHICAGO 

WINDSOR  &  KENFIELD  PUBLISHING  CO. 

1903 


COPYRIGHT  1898 
BY  WINDSOR  &  KENFIELD  PUBLISHING  Co. 

COPYRIGHT  1903 
BY  WINDSOR  &  KENFIELD  PUBLISHING  Co. 


INTRODUCTION. 


The  purpose  of  this  work  is  to  so  iamiliarize  the  reader 
with  the  operation  of  an  electric  car,  that  the  practical  du- 
ties of  a  motorman  may  be  the  more  easily  and  quickly 
learned.  At  the  same  time  it  will  be  found  to  explain,  in 
simple  language  devoid  of  mathematics  and  technicalities, 
many  points  not  generally  understood  by  the  average  mo- 
torman, and  a  knowledge  of  which  cannot;  fail  to  make  his 
services  more  valuable  to  his  company  and  satisfactory  to 
himself;  and  also  to  better  fit  him  for  promotion. 

The  motorman  who  understands  his  business  is  able  to 
operate  the  cars  that  are  put  in  his  charge  with  much  less 
danger  of  accident,  and  with  less  power  and  less  wear  on 
the  equipment,  than  a  man  who  simply  knows  how  to  get 
his  car  over  the  road  on  time.  This  book  is  not  only  in- 
tended to  explain  the  electrical  part  of  an  electric  motor 
car,  but  to  give  some  general  instruction  and  advice,  to 
those  who  desire  to  make  this  work  their  livelihood.  It  is 
based  on  the  experience  gathered  for  a  number  of  years 
in  the  electric  railway  field,  instructing  motormen  in  their 
duties  and  work,  and  on  results  and  observations  made  on 
roads  in  practical  life.  To  explain  some  electrical  effects 
it  has  been  necessary  to  adopt  a  few  comparisons,  which, 
while  not  exactly  correct  from  a  scientific  standpoint,  give 
the  reader  a  clear  picture  of  what  is  meant. 

By  closely  reading  this  book  and  following  the  advice 
given  the  reader  should  be  able  to  acquire  a  responsible  vo- 
cation in  a  comparatively  short  time,  and  he  has  the  assur- 
ance that  he  does  not  drop  into  it  in  a  haphazard  fashion, 


but  has  a  guide  to  lead  him  over  a  road  yet  unknown  to 
him,  a  road  which  is  made  considerably  shorter  and 
smoother  by  this  method  than  learning  entirely  from  ex- 
perience. 

In  securing  illustrations  and  collecting  data  for  describ- 
ing the  electric  machines  and  devices,  the  author  desires  to 
acknowledge  the  generous  assistance  of  the  manufacturing 
companies  whose  apparatus  is  explained  in  the  following 
pages. 

This  work  is  divided  into  two  parts.  Part  I.  treats  of 
the  practical  work  of  a  motorman.  Part  II.  will  be  found 
to  explain  more  in  detail  the  theory  and  construction  of 
the  apparatus. 

THE  AUTHOR. 


CHAPTER   I. 

A  GLANCE  OVER  THE  CAR  EQUIPMENT. 

A  man  who  will  read  and  study  as  well  as  gain  from  prac- 
tical experience  will  be  worth  a  great  deal  more  than  the 
average  motorman  of  today,  and  he  should  be  able  to  se- 
cure a  position  more  readily.  Experience  has  shown  that  a 
motorman  who  is  familiar  with  the  track,  switches  and 
curves  and  who  has  been  in  the  employ  of  the  company  for 
some  time  can  operate  a  car  with  a  very  much  smaller  cur- 
rent consumption  than  a  new  man.  It  is  the  same  compar- 
ison of  an  experienced  and  inexperienced  fireman  in  the 
boiler  room.  It  is  evident  that  the  more  a  man  knows  about 
his  vocation  the  better  compensation  he  can  expect.  A  man 
may  start  as  a  motorman  and  by  faithful  service  and  study 
he  may  advance  to  be  a  car  inspector,  line  inspector  and 
eventually  electrician  of  the  road. 

A  man  wishing  to  qualify  himself  for  a  motorman  can  ad- 
vance in  two  ways  :  by  experience  in  operating  a  car  and  by 
studying  the  theory  of  the  electrical  equipment.  For  rapid 
advancement  the  practical  work  should  be  accompanied  by 
electrical  reading. 

The  reader  who  wishes  to  become  proficient  and  know 
more  than  just  simply  enough  to  run  his  car  over  the  road, 
should  be  of  a  practical  and  mechanical  turn  of  mind.  He 
should  know  something  about  the  use  of  tools  and  machin- 
ery. To  become  familiar  with  the  electric  car  equipment 
the  best  plan  is  to  work  at  first  in  the  barns  and  repair 
shops.  One  will  there  learn  the  practical  side.  He  will 


10 


11 

have  to  mount  motors  on  trucks  or  repair  defective  pieces 
of  machinery,  and  by  frequently  handling  them  he  will  soon 
familiarize  himself  with  their  names  and  uses.  However, 
not  everyone  can  have  such  preparation  for  a  position  as 
motorman,  and  for  this  reason  we  will  do  the  next  best 
thing,  namely,  take  an  imaginary  trip  through  the  car  shop 
and  mention  briefly  the  various  parts  of  an  electric  car 
equipment  and  the  devices  that  are  necessary  to  operate  it. 
Then  these  devices  will  be  described  in  detail  further  on 
and  the  principles  on  which  they  work  will  be  explained. 

To  begin  with,  we  see  trolley  wires  entering  the  repair 
shop  and  cars  brought  in  and.  taken  out.  Now,  there  are 
many  persons  who  have  seen  this  done,  but  few  understand 
the  operation  in  its  details  and  the  many  devices  and  ap- 
pliances that  are  necessary  to  accomplish  it. 

The  electric  current  as  it  flows  in  the  wires  is  invisible, 
and  although  they  look  "dead"  to  us  they  may  be  transmit- 
ting hundreds  of  horse  power  of  energy.  It  is  necessary  to 
be  cautious  about  coming  in  contact  with  suspended  wires 
and  nothing  should  be  touched  that  may  be  connected  in 
any  way  with  a  circuit  or  a  severe  shock  will  be  received. 

A  motor  car  is  composed  of  the  following  essential  parts : 

1.  A  car  body  for  carrying  the  passengers. 

2.  A  car  truck  and  wheels  for  carrying  the  motors  and 
car  body. 

3.  Motors  for  propelling  the  car. 

4.  A  trolley  for  taking  the  power  from  the  overhead 
wire. 

5.  Controllers  for  admitting  current  to  the  motor  wind- 
ings and  regulating  the  amount  of  power  conducted  to  the 
motors. 

6.  Brakes  for  stopping  the  car. 

7.  Devices  for  protecting  the  motors,  such  as  fuses, 
lightning  arresters  and  switches. 


12 


Figs,  i  to  4  show  different  constructions  of  car  trucks,  but 
these  are  only  a  few  of  the  types  which  are  in  general  use. 


Figs,  i  and  2  show  different  styles  of  single  trucks  which  are 
used  on  short  cars  of  from  25  to  30  ft.  in  length.  Figs.  3 
and  4  show  bogie  trucks  which  are  used  with  long  cars,  two 


such  trucks  being  used  under  each  car.     The  essential  parts 
of  all  street  car  trucks  consist  of  two  sets  of  wheels  mounted 


13 


on  axles  which  are  held  in  position  by  bearings.  The  bear- 
ings are  fixed  to  the  side  frames  which  give  the  truck  its 
rigidity.  Springs  are  placed  between  the  bearings  and  the 
parts  on  which  the  car  body  rests  in  order  to  prevent  too 
severe  jarring  of  the  car  body.  In  the  case  of  the  single 
trucks  the  lower  sills  of  the  car  are  bolted  directly  to  the  side 
frames  of  the  truck,  but  where  double  trucks  are  used  a  piece 
known  as  the  truck  bolster  extends  between  the  two  side 


frames  and  is  pivoted  at  its  center  to  the  car  body  bolster. 
The  brake  rigging  is  also  a  very  important  part  of  the  equip- 
ment of  the  truck,  and  on  most  modern  electric  cars  both 
hand  and  power  brakes  are  used.  The  brakes  and  brake 
rods  are  shown  on  the  trucks  illustrated,  and  are  of  a  num- 
ber of  different  patterns,  some  of  which  will  be  described  in 
a  later  chapter.  The  location  of  the  brake  shoes  is  normally 
from  ^  to  34  m-  distant  from  the  wheels.  Fig.  5  shows  a 
car  mounted  upon  a  single  truck  and  Fig.  6  shows  a  double 
truck  car. 


14 


An  electric  railway  motor  mounted  on  an  axle  between 
the  car  wheels  is  shown  in  Fig.  7.  The  wheels  and  axle 
have  been  taken  from  underneath  the  truck.  The  motor 
consists  of  two  principal  parts ;  the  outer  case,  which  is 
called  the  field  magnet  and  which  is  stationary,  and  an  inner 
rotating  part  called  the  armature.  The  electric  motor  and 
the  principles  governing  it  will  be  explained  in  a  subsequent 


FIG.  8. 


chapter.  Figs.  7  and  8  give  a  general  idea  of  the  appear- 
ance of  the  motor  and  may  be  referred  to  together.  On  one 
end  of  the  armature  shaft  6  is  keyed  a  pinion  B  as  shown  in 
Fig.  8,  but  in  service  the  pinion  and  the  gear  into  which  it 
meshes  are  covered  by  a  casting  as  B1  C]  in  Fig.  7.  This 
pinion  meshes  with  a  split  gear  which  is  fastened  on  the  car 
axle.  The  car  axle  passes  through  the  bearing  5  as  shown 
m  Fig.  9. 


15 


Fig.  10  shows  one  form  of  split  gear  which  is  mounted  on 
the  car  axle  and  engages  with  the  pinion  B.  The  manner  in 
which  the  car  is  propelled  will  now  be  made  clear.  In  start- 
ing the  car  a  current  is  sent  into  the  motor  which  causes  the 
armature  to  revolve  and  with  it  the  pinion  B.  This  pinion 
meshes  with  the  teeth  of  the  split  gear  C  and  turns  it  in  a 
direction  opposite  to  which  the  pinion  rotates.  (See  Fig. 


FIG.  9. 


8.)  As  the  pinion  B  is  much  smaller  in  diameter  than  the 
split  gear  C,  the  car  axle  to  which  C  is  rigidly  attached 
makes  a  less  number  of  revolutions  than  does  the  pinion 
which  drives  it.  In  this  way  the  power  developed  in  the 
motor  is  transmitted  through  the  gears  to  the  car  axle  and 
the  speed  of  the  latter  is  much  less  than  that  of  the  motor 
armature.  We  will  now  continue  to  discuss  the  essential 
parts  of  a  car  equipment,  and  after  we  have  gone  through 


16 

the  repair  shop  in  this  way  we  will  take  up  in  the  subsequent 
chapters  the  theory  of  these  devices  and  parts,  and  explain 
their  construction  and  functions. 

Returning  to  Fig.  8,  if  the  power  admitted  to  the  motor 
turns  the  armature  shaft  6  and  pinion  B  in  the  direction  in- 
dicated by  the  arrow,  then  the  gear  C  will  revolve  in  the  op- 


FIG.  19. 


posite  direction  and  the  car  wheel  2  will  move  from  right  to 
left  as  indicated  by  the  arrow.  The  functions  of  the  casing 
B1  is  to  protect  the  pinion  and  gear  wheel  from  dirt  and 
mechanical  injury  and  if  filled  with  a  heavy  grease  the  gears 
are  thus  lubricated  and  preserved  and  at  the  same  time  the 
noise  which  they  make  in  running  is  by  this  means  greatly 
reduced.  In  all  of  the  motors  illustrated  a  lid  will  be  noticed 
over  the  commutator  end  of  the  frame  where  the  brushes 


17 

are  located.  These  lids  are  readily  removed  and  their  object 
is  to  facilitate  inspection  of  the  commutator  and  brushes. 
Other  lids  cover  holes  usually  provided  for  supplying  oil 
to  the  bearing  surfaces.  It  will  be  noticed  that  all  of  the 
motors  illustrated  have  their  field  magnets  designed  so  as  to 
entirely  enclose  the  interior  parts,  and  all  the  joints  of  the 
outer  frame  are  made  tight  enough  to  be  practically  water 


proof.  Water  and  dirt  would  readily  be  thrown  into  the 
motor  from  the  car  wheels  if  the  parts  were  not  tightly 
enclosed,  but  by  having  the  motor  cased  the  windings  are 
protected  from  water  which  would  cause  them  to  rapidly 
burn  out. 

Figs,  ii  and  12  show  two  views  of  a  street  car  motor 
with  the  frame  dropped.     Fig.  1 1  shows  the  lower  frame  of 


18 

the  motor  dropped  leaving  the  armature  in  position.  The 
method  of  dividing  field  magnets  horizontally  through  the 
bearings  and  fastening  the  lower  part  at  one  side  by  means 
of  hinges  is  the  most  usual  arrangement  for  providing  for 
the  inspection  and  repairs  of  the  interior  parts  of  the  motor. 


FIG.  12. 


Fig.  12  shows  the  lower  frame  dropped  and  with  it  the  arma- 
ture which  is  ready  for  removal. 

In  suspending  motors  upon  car  trucks  one  side  of  the 
motor  is  always  held  in  position  by  the  bearings  upon  the 
car  axle.  The  other  side  of  the  motor  is  not  fastened  rigidly 
to  the  frame  of  the  truck,  but  has  springs  placed  at  some 


19 

point  between  the  motor  and  the  frame  in  order  to  avoid  the 
sudden  jar  which  would  be  occasioned  in  starting  the  motor 
if  it  were  rigidly  connected.  These  springs  also  serve  to 


greatly  increase  the  life  of  the  gear  wheels  as  part  of  the 
shock  in  starting  is  taken  up  by  these  springs,  without  which 
the  teeth  would  be  liable  to  be  stripped  from  the  gears. 
Figs.  13,  14  and  15  represent  the  same  motor  with  different 


styles  of  suspension.  Fig.  13  shows  what  is  called  the 
cradle  suspension  which  consists  of  an  iron  bar  resting  on 
powerful  springs  which  in  turn  rest  on  the  truck.  This 
method  is  designed  to  relieve  the  motor  bearings  of  the 


20 

weight  of  the  motor,  which  being  suspended  in  the  line  of 
its  center  of  gravity  is  supported  without  undue  strains. 


Fig.  14  shows  the  parallel  bar  suspension  and  Fig.  15  the 
nose  suspension.  The  latter  is  the  one  most  commonly 
used. 


FIG.  16, 


A  type  of  motor  differing  in  some  respects  to  those  pre- 
viously illustrated  is 'shown  in  Fig.  16.     This  is  known  as 


21 


the  box  frame  type  and  it  differs  from  the  split  frame  type 
in  that  the  magnet  frame  is  cast  in  practically  one  piece 
forming  a  cube  with  well  rounded  corners  and  large  open- 
ings at  each  end  into  which  the  frames  carrying  the  bearings 
for  the  armature  shaft  are  bolted.  The  armature  is  put  in 
place  or  removed  through  these  end  openings  in  the  frame. 
Motors  of  this  type  are  mounted  or  moved  from  the  truck 
by  means  of  a  crane  from  above  when  the  truck  is  out  from 
under  the  cars,  and  no  track  pit  is  required.  In  order  to 


FIG.  17. 


facilitate  removing  the  armatures  from  these  motors  a  spe- 
cial tool  is  provided,  shown  in  Fig.  17,  upon  which  the  motor 
is  mounted.  The  armature  shaft  is  centered  on  this  tool 
and  by  removing  the  bolts  from  one  of  the  frame  heads  and 
moving  the  motor  frome  to  one  end  of  the  tool  by  means  of 
the  hand  wheel,  the  armature  is  left  entirely  exposed  and 
mounted  upon  centers  where  it  may  be  readily  inspected  or 
repaired. 

Fig.  1 8  is  a  diagram  of  the  wiring  in  a  car.     The  two 
controllers  are  represented  at  the  extreme  ends  and  the  four 


23 

car  wheels  are  indicated  by  1,2,  3  and  4 ;  between  these  four 
wheels  are  shown  the  outlines  of  the  two  motors.  Heavy 
tube-like  connection  from  the  controllers  to  the  motors 
represents  a  hose  which  surrounds  the  wires  going  to  each 
motor.  It  protects  them  partly  from  mechanical  injury  and 
partly  from  dampness,  and  water  thrown  by  wheels  or  rails. 
The  box  marked  "resistance"  is  used' in  starting  the  car  and 
will  be  explained  in  the  chapter  on  controllers.  The  resist- 
ance, hose  and  other  devices  are  beneath  the  car  floor.  One 
wire  entering  the  hose  comes  from  the  trolley.  This  wire 


is  led  from  the  roof  of  the  car  down  the  corner  post  and 
passes  through  the  lightning  arrester  and  fuse  box. 

There  are  many  styles  of  trolley  bases.  In  Figs.  19  and 
20  two  forms  are  shown.  The  trolley  wire  is  generally  at- 
tached to  the  iron  base  below  a  screw  provided  with  one  or 
two  washers.  The  springs  are  employed  for  the  purpose  of 
causing  an  upward  pressure  on  the  trolley  pole,  which  is  not 
shown.  The  pole  can  be  removed  from  the  trolley  base  and 
is  held  adjustably  in  a  socket.  A  great  range  of  movement 
is  necessary  in  the  springs  and  trolley  pole  as  the  trolley 


24 

wire  (the  wire  suspended  in  the  air)  cannot  be  attached  at 
the  same  height  over  all  the  course  of  travel.  For  instance, 
at  railroad  crossings  it  is  placed  much  higher  so  as  not  to 
interfere  with  the  railroad  service  and  brakemen  who  may 
be  standing  on  the  roofs  of  the  cars  ;  again  it  may  be  much 
lower  in  other  places,  such  as  bridges  and  tunnels.  The 
trolley  pole  is  a  long"  iron  or  wooden  pole  on  the  end  of 
which  is  located  the  "trolley."  This  trolley,  which  consists 
of  brass  or  gun  metal,  is  generally  a  small,  narrow  wheel 
with  projecting  flanges,  though  some  European  roads  use  a 


FIG.  20. 

straight  horizontal  rod  which  slides  along  under  the  trolley 
wire. 

The  brake  staff  used  on  nearly  all  electric  cars  is  very 
simple.  However,  the  arrangement  of  levers  on  different 
makes  of  trucks  varies  greatly,  and  as  a  knowledge  of  the 
brake  and  how  to  use  it  is  one  of  the  most  important  things 
for  a  motorman  to  know,  the  subject  of  brakes  will  also  be 
taken  up  in  a  chapter  by  itself. 

To  make  our  examination  of  a  motor  car  equipment  com- 
plete we  have  yet  to  notice  two  overhead  or  "canopy' 
switches,  usually  located  under  the  hood  above  the  platforn 
on  each  end  of  the  car.  Pushing  the  handle  of  either  one  o/ 
these  to  the  "off"  position  opens  the  circuit  and  cuts  off  ail 
the  current  to  controllers  and  motors,  just  as  if  the  trolley 


25 

wheel  had  been  pulled  from  the  wire,  so  that  the  motors  and 
controllers  may  be  safely  examined  and  handled.  A  small 
switch  is  usually  located  inside  the  car  near  one  door  for 
turning  the  lamps  on  and  off.  If  the  car  has  electric  heaters 
another  switch  is  also  provided  for  turning  them  on  and  off. 
A  fuse  box  or  an  automatic  circuit  breaker  will  usually  be 
found  upon  a  car.  The  purpose  of  each  of  these  devices  is 
to  automatically  open  the  electric  circuit  whenever  the 
amount  of  current  used  becomes  so  large  that  it  will  injure 
the  motors.  The  construction  and  action  of  these  devices 
will  be  explained  in  a  subsequent  chapter.  Somewhere 
upon  the  car  (usually  beneath  it)  will  be  found  a  safety  de- 
vice called  a  lightning  arrester  which  is  intended  to  prevent 
lightning  from  reaching  the  motors.  As  lightning  readily 
pierces  any  insulating  material,  this  device  is  designed  to 
deflect  the  lightning  into  the  ground  before  it  reaches  or 
passes  through  the  motors. 


CHAPTER  II. 

TRANSMITTING  ELECTRIC  POWER. 

In  order  to  convey  electric  power  to  a  distance  certain 
precautions  are  necessary.  The  electric  current  has  to  be 
guided  by  means  of  a  conductor,  which  in  practice  is  gener- 
ally copper  wire,  and  in  order  that  the  energy  transmitted 
shall  be  wasted  as  little  as  possible  the  conducting  wire  must 
be  thoroughly  insulated  from  the  earth  and  from  all  other 
conducting  bodies.  It  was  found  at  an  early  day  that  there 
is  a  great  deal  of  difference  in  conductivity  between  different 
substances,  and  that  some  conduct  the  current  very  easily, 
others  less  easily,  and  again  others  do  not  conduct  the  cur- 
rent at  all  unless  it  is  forced  through  them  under  very  high 
pressure.  The  first  class  of  substances,  which  are  known 
as  good  electrical  conductors,  includes  all  metals,  and  of  the 
metals  the  best  conductors  are  silver  and  copper.  The  last 
class  of  materials,  which  do  not  conduct  electric  current,  are 
called  non-conductors  or  insulators,  and  if  a  conductor  is  at- 
tached or  supported  upon  a  non-conducting  substance  the 
conductor  is  insulated  from  the  ground  to  which  the  current 
tends  to  flow  in  the  endeavor  to  establish  an  equilibrium  of 
the  forces  acting.  Thus,  if  we  should  lay  bare  electric  wires 
in  the  ground  we  would  receive  but  little  current  at  the  far 
end  because  the  earth  is  itself  a  conductor  of  electricity  and 
would  absorb  the  greater  part  of  the  current  in  the  wire.  It 
is  evident  therefore  that  the  conductor  must  be  insulated 
from  the  earth  and  from  all  other  conductors  in  order  to 


27 


transmit  the  current  to  a  distant  point  where  it  is  to  be  con- 
sumed. Perfectly  dry  air  is  one  of  the  best  insulators 
known,  while  water  containing  dissolved  salts  and  other  im- 
purities, as  generally  found,  is  an  excellent  conductor. 
There  is  little  chance  for  current  to  escape  from  a  wire  sup- 
ported on  insulating  material  unless  moisture,  acids  or  dirt 
is  to  be  found  on  the  surface  of  the  insulators,  in  which  case 
a  slight  leakage  through  the  dirt  or  moisture  will  occur. 


SECTION  INSULATOR 


FIG.  21. 


The  best  and  most  commonly  used  insulating  substances  are 
porcelain,  glass,  mica,  rubber,  dry  wood,  silk,  shellac,  paper, 
cotton,  etc. 

To  transmit  electricity  from  one  place  to  another  a  certain 
amount  of  energy  has  to.be  spent  in  the  transmission  which 
is  no  longer  available  for  useful  work.  This  loss  of  energy 
is  due  to  the  resistance  of  the  conductor  which  carries  the 
current,  and  will  be  readily  understood  by  the  analogy  of 


28 

water  flowing  through  a  pipe.  If  we  transmit  a  volume  of 
water  to  a  distance  through  a  pipe  under  a  certain  pressure 
the  pressure  of  the  water  at  the  further  end  of  the  pipe  will' 
be  considerably  less  than  the  pressure  at  the  point  where  the 
water  enters  the  pipe.  This  loss  of  pressure  is  due  to  the 
friction  of  the  water  against  the  walls  of  the  pipe  and  it  will 
be  readily  seen  is  greater  the  greater  the  length  of  the  pipe, 
and  will  be  less  for  a  given  volume  of  water  as  the  size  of 
the  pipe  is  larger.  In  the  same  way  with  an  electric  current, 
the  longer  the  conducting  wire  the  greater  will  be  the  resist- 
ance, while  by  increasing  the  diameter  of  the  wire  the  resist- 
ance will  be  reduced.  The  smaller  the  amount  of  loss  in  the 
transmitting  lines  the  more  economical  is  the  working  of  the 
system. 

We  have  spoken  of  the  volume,  pressure  and  resistance 
of  water  in  a  pipe  as  being  analagous  to  volume,  pressure 
and  resistance  of  current  flowing  through  a  conductor.  The 
electrical  unit  of  quantity  corresponding  to  the  volume  of 
water  is  called  the  ampere.  The  electrical  unit  of  pressure 
is  called  the  volt,  and  the  unit  of  electrical  resistance  is  the 
ohm.  According  to  Ohm's  law  the  current  in  amperes 
equals  the  pressure  in  volts  divided  by  the  resistance  in 
ohms.  This  laws  is  generally  expressed  by  the  equation  : 


R 

in  which  C  =  current  in  amperes 

E  =  electromotive  force  in  rolts 
R  =  resistance  in  ohms 

The  electric  current  has  to  be  produced  in  most  cases  by 
operating  a  dynamo  by  means  of  a  steam  engine,  and  this 
engine  receives  its  energy  from  the  boiler  under  which  coal 
is  burned.  The  energy  located  in  the  coal  is  utilized  to  evap- 


29 

orate  the  water  in  the  boiler  and  the  steam  so  produced 
actuates  the  engine,  which  in  turn  operates  the  dynamo. 
The  greater  the  waste  in  electricity,  the  greater  will  be  the 
coal  consumption  per  month.  Therefore,  engineers  strive 
to  avoid  losses  as  much  as  possible,  such  as  leakage  on  elec- 
tric lines  or  faults  or  leakage  on  devices  connected  therewith, 
as  they  form  part  of  the  circuit  the  moment  the  current  is 
allowed  to  pass  into  them.  For  this  reason  motors,  con- 
trollers and  other  parts  attached  to  the  car  are  highly  insu- 
lated, and  the  overhead  conductor  is  held  in  position  by  in- 
sulators, of  hard  rubber,  glass,  porcelain,  compounds  of  mica, 
or  other  substances  put  into  suitable  shape  under  great  pres- 
sure. Some  such  insulators  as  used  on  electric  railwavs  are 


FIG.  22. 

shown  in  Fig.  21.  In  most  cases  they  consist  of  two  metallic 
parts  which  are  separated  from  one  another  by  a  strong  and 
heavy  layer  of  insulation.  The  one  metallic  part  is  then  con- 
nected to  the  conductor  which  is  to  carry  the  electric  current, 
while  the  other  is  attached  to  a  pole,  or  span  wire.  This  lat- 
ter may  be  regarded  as  connected  to  the  earth,  but  the  other 
end  is  insulated  from  such  contact  by  the  interposed  layer  of 
non-conducting  material.  Fig.  22  shows  such  an  insulator 
in  section  disclosing  its  construction. 

The  various  steps  in  the  generation  and  use  of  the  elec- 
tric current  may  be  enumerated  as  in  the  following  manner : 
Fig.  23  shows  a  boiler  room  of  a  street  railway  station  and 
the  steam  here  generated  is  conducted  by  the  steam  mains 
or  pipes  to  the  engine  and  dynamo  room,  Fig.  24.  In 


30 


31 


neary  every  station  the  arrangement  of  machines  is  differ- 
ent ;  in  some,  the  engine  drives  the  dynamo  by  means  of  a 
belt,  but  in  most  of  the  larger  stations  the  dynamo  is  now 
direct  connected,  or  in  other  words  the  armature  of  the  dy- 
namo is  carried  on  the  engine  shaft,  as  shown  in  Fig.  25. 
The  current  is  controlled  by  the  use  of  a  switchboard 
through  which  the  dynamos  are  connected  to  the  feeders 
or  outgoing  wires.  Fig.  26  represents  switchboard  in  a 
street  railway  station,  upon  which  are  switches  for  opening 


and  closing  circuits,  circuit  breakers  for  protecting  the  dy- 
namos from  overloads,  voltmeters  for  indicating  the  volt- 
age and  ammeters  for  indicating  the  amount  of  current 
flowing  through  the  circuits. 

The  electrical  transmission  from  a  railway  power  station 
is  shown  in  diagram  in  Fig.  27.  To  the  left  will  be  noticed 
the  dynamo,  which  is  connected  by  means  of  a  commutator 
brush  to  the  trolley  wire  (all  switches,  circuit  breakers, 
safety  devices,  etc.,  at  the  station  and  on  the  car  have  been 
omitted  for  the  sake  of  clearness  and  simplicity).  Each 


32 


electric  car  is  indicated  by  one  motor,  wheel,  trolley  and 
controller.    By  following  the  arrows  it  will  be  observed  that 


the  electric  current  starts  from  the  dynamo,  goes  to  the 
trolley  wire,  from  there  to  the  trolley  wheels  and  to  the 


33 


controllers ;  from  the  controllers  to  the  motors,  the  wind- 
ings of  which  are  indicated  by  a  few  turns,  and  from  there 
to  the  iron  body  of  the  motor,  to  the  car  wheel  and  to  the 
rail.  Through  the  rails  and  return  feeders  it  flows  back  to 


FIG.  27. 

the  station,  where  the  second  brush  of  the  dynamo  is  con- 
nected to  the  rail.  This  completes  a  circuit,  through  the 
dynamo,  out  over  the  trolley  wire,  down  through  the  motor 
and  back  through  the  rails,  and  current  flows  over  this  cir- 
cuit whenever  a  controller  is  put  in  operation. 


CHAPTER  III. 

OPERATION  OF  CARS  AND  CONTROLLERS. 

The  value  of  any  motorman  depends  on  the  economy 
with  which  he  can  operate  his  car ;  economy  in  the  way  of 
preventing  costly  accidents,  economy  in  power  and  econ- 
omy in  wear  and  tear  of  the  cars,  trucks  and  motors  he 
runs.  What  has  been  said  before  has  been  intended  to  pre- 
pare the  reader  for  this  chapter,  which  deals  directly  with  a 
motorman's  actual  duties.  It  does  not  require  any  special 
knowledge  to  be  able  to  get  a  car  over  the  road.  To  oper- 
ate it  in  the  best  possible  manner  is  quite  another  matter. 
It  is  the  main  object  of  this  book  to  tell  a  motorman  how 
to  make  himself  a  valuable  man ;  how  to  operate  a.  car  with 
greatest  economy. 

Let  us  first  learn  something  about  the  operation  of  con- 
trollers, beginning  with  the  series-parallel  controllers  which 
are  in  common  use  today.  The  operation  of  all  the  control- 
lers is  very  simple.  They  all  have  reverse  levers  at  the  right 
of  the  stand  or  on  the  top,  and  the  controlling  handle  on  all 
is  moved  around  in  the  direction  of  the  hands  of  a  watch  to 
turn  on  the  current,  and  in  the  opposite  direction  to  turn 
off  the  current.  Before  trying  to  start  a  car,  first  be  sure 
that  the  brakes  are  off,  that  the  controller  handle  at  the 
other  end  of  the  car  is  on  the  "off"  position  and  the  canopy 
switches  are  closed.  Then  move  the  controller  handle  to 
the  first  notch.  The  car  will  start  if  all  is  right.  After  the 
car  is  well  under  way  on  the  first  notch,  move  to  the  second, 
and  so  on  to  the  last.  In  moving  from  one  notch  to  an- 
other do  not  stop  the  handle  between  notches,  but  give  it 


35 

a  push  strong  enough  so  that  it  will  go  to  the  next  notch. 
A  timid  or  inexperienced  motorman  is  apt  to  turn  the 
handle  slowly,  but  this  is  bad  practice. 

Always  wait  long  enough  on  each  notch  for  the  car  to 
gain  speed  before  passing  to  the  nex-t  notch.  If  you  do  not 
do  this,  much  more  current  than  necessary  may  be  used  to 
move  the  car.  The  wheels  may  slip,  the  motors  will  be 
strained  and  overheated  and  there  will  be  a  great  drain  on 
the  power  house  generators,  and  wear  on  machinery. 
When  the  notch  is  reached  where  the  motors  are  in  series 
and  there  is  no  rheostat  resistance  in  the  circuit,  special 
care  should  be  taken  to  let  them  gain  speed  and  run  up  to 
nearly  the  maximum  speed  they  can  attain  in  this  position 
before  passing  to  the  higher  notches  where  the  motors  are 
in  parallel.  When  the  motors  are  thrown  in  parallel  too 
soon  in  starting,  a  waste  of  power  takes  place.  This  notch 
on  which  the  motors  are  in  series  with  no  rheostat  resist- 
ance in  the  circuit  is  the  third  point  on  the  Westinghouse 
G,  No.  14,  No.  28,  No.  29,  the  Walker  J,  and  the  General 
Electric  K  controllers.  It  is  the  fourth  point  on  the  Gen- 
eral Electric  K-2,  the  Westinghouse  No.  28-A  and  No.  38, 
the  Walker  S  and  the  Steel  Motor  Company's  C  control- 
lers. It  is  on  this  series  point  that  the  motors  exert  the 
greatest  pull  with  the  least  current,  and  it  should  prefer- 
ably be  used  when  there  is  heavy  pulling  to  be  done  or  steep 
grades  to  be  climbed. 

On  looking  at  the  points  marked  on  the  controller  tops, 
we  see  that  some  of  them  are  marked  with  longer  or  heav- 
ier marks  than  the  others.  Those  points  with  long  marks 
are  called  "running"  points,  because  on  them  the  motors 
may  be  operated  for  any  length  of  time  without  overheat- 
ing or  wasting  current  in  the  rheostats.  Among  these  run- 
ning points  there  are  some  to  be  preferred  because  on  them 
the  whole  energy  taken  into  the  motors  is  used  to  propel 


36 

the  car.  These  preferred  points  are  those  positions  on 
which  no  rheostat  resistance  or  diverter  is  left  in  circuit 
with  the  motors. 

The  K  and  K-2  controllers  have  four  preferred  running 
points.  On  the.K  controller  the  first  preferred  running 
point  reached  is  the  third,  at  which  the  motors  are  in  series 
and  resistance  all  cut  out.  This  should  be  used  for  slow 
running.  It  gives  a  little  less  than  half  full  speed.  The 
fourth  or  next  point  is  also  a  running  position.  It  gives 
half  full  speed  and  may  be  used  for  running  along  on  a  level, 
but  should  never  be  used  on  a  grade  or  for  heavy  pulling. 
The  sixth  point  on  the  K  controller  is  also  a  preferred  run- 
ning point,  as  is  the  seventh.  The  latter  should  only  be 
used  for  highest  speed  on  a  level,  as  on  it  the  fields  are 
shunted,  as  on  the  fourth  point.  On  the  K-2  controller,  the 
fourth  and  fifth  and  the  eighth  and  ninth  points  are  the  pre- 
ferred running  points.  The  fourth  here  corresponds  to  the 
third  on  the  K  controller  and  the  fifth  here  to  the  fourth 
on  the  K,  and  the  fifth  should  be  used  in  the  same  way  as 
the  fourth  on  the  K.  The  eighth  and  ninth  points  of  the 
K-2  are  the  high  speed  points,  the  ninth  being  only  for  use 
on  a  level.  Use  of  the  fifth  or  ninth  points  on  grades  is 
very  wasteful  of  current  and  hard  on  the  motors,  and  little 
is  gained  by  it  in  the  way  of  speed.  The  same  is  true  of  the 
fourth  and  seventh  points  on  the  K  controller. 

In  the  Westinghouse  controllers,  the  third  point  in  the 
G,  No.  14,  No.  28,  No.  28-A  and  29  is  the  first  preferred 
.position.  In  the  No.  38  Westinghouse  it  is  the  fourth,  in 
which  the  motors  are  in  series  without  resistance.  In  the 
J  controller  of  the  Walker  Company  it  is  the  third  point, 
and  in  that  of  the  Steel  Motor  Company  it  is  the  fourth 
point. 

The  second  preferred  running  position  in  all  of  them  is 
when  the  motors  are  at  maximum  speed.  The  Steel  Motor 


37 

Company  has  on  some  motors  and  controllers  a  third  such 
point,  that  is  point  9,  which  is  used  when  a  shunt  is  pro- 
vided in  the  field  magnet  winding"  of  the  motors. 

In  shutting  off  current  the  controller  handle  should  be 
brought  rapidly  to  the  off  position  from  whatever  point  it 
may  happen  to  be  on,  without  stopping  at  any  point.  To 
run  the  car  backward  when  it  is  standing,  pull  the  reverse 
lever  back  and  turn  on  the  current  as  when  running  for- 
ward. Sometimes  it  is  necessary  to  reverse  when  the  car  is 
running  ahead,  to  avoid  running  into  something.  To  do 
this,  throw  controller  handle  to  "off"  and  pull  back  reverse 
handle.  Then  move  controller  to  the  first  notch.  Tire  car 
will  stop  with  a  jerk  and  begin  to  go  backward.  This  way 
should  be  resorted  to  only  when  there  is  danger,  and  even 
then  the  car  speed  should  be  slow,  because  it  is  not  a  sure 
remedy.  The  fuse  may  blow  and  so  suddenly  shut  off  the 
power  on  account  of  the  abnormally  heavy  current  flowing. 
There  is  also  a  possibility  that  one  or  the  other  motor 
may  be  permanently  disabled. 

There  is,  however,  one  way  in  which  a  violent  stop  can 
be  made  with  a  series-parallel  controller,  even  when  the 
power  is  cut  off  and  the  brakes  fail.  It  is  done  by  revers- 
ing and  putting  the  controller  handle  on  the  highest  point 
of  the  controller.  In  this  case  the  motors  act  as  dynamos, 
generating  current.  This  method  may  be  used  in  emer- 
gencies when  the  brakes  are  not  sufficient  and  the  trolley 
has  come  off  or  the  fuse  has  blown  and  the  car  is  going 
down  an  incline.  You  may  never  have  to  use  it,  and  it  is 
not  creditable  to  have  to  use  it  by  letting  a  car  get  beyond 
control.  But  the  brake  may  give  out  or  something  else 
happen  beyond  the  control  of  the  motorman,  so  it  should 
always  be  remembered,  as  it  may  save  you  a  sad  accident 
some  day.  In  case  you  have  reversed  and  the  fuse  blows, 
the  instant  you  feel  that  the  power  has  been  shut  off  by 


38 

the  blowing  of  the  fuse,  put  your  controller  around  on  one 
of  the  higher  points  named.  This  plan  may  also  be  used 
in  case  the  brakes  fail  and  the  trolley  comes  off  going  down 
hill.  It  is  a  very  violent  way  of  stopping,  and  injurious  to 
the  equipment.  On  the  Walker  S  controller  the  emergency 
brake  notch  on  the  reverse  switch  should  be  used  instead 
of  reversing,  as  explained  in  chapter  on  controllers  in 
Part  II. 

The  Westinghouse  D  controller,  the  old  Edison  and 
Sprague  controllers  are  different  both  in  construction  and 
operation  from  the  series-parallel  controllers  just  men- 
tioned. When  their  handles  are  at  "off"  they  point  straight 
backwards.  There  is  no  separate  reverse  lever.  Turning 
the  handle  to  the  left  from  the  off  position  runs  the  car  for- 
ward. Turning  the  handle  to  the  right  runs  the  car  back- 
ward. In  starting  a  car  with  the  Westinghouse  D  control- 
lers, advance  the  handle  firmly  from  notch  to  notch,  as  with 
the  series-parallel  controller,  pausing  after  each  notch  long 
enough  to  let  the  car  get  up  to  speed. 

On  the  top  of  the  Edison  and  Sprague  controllers  points 
are  cast  which  indicate  the  contact  positions  on  the  control- 
ler drum.  The  motorman  should  stop  long  enough  in  each 
position  to  allow  the  motor  to  get  up  to  speed.  Reversing 
or  running  backwards  is  accomplished  in  all  of  these  con- 
trollers simply  by  moving  the  handle  around  from  "off"  to 
the  right  side  of  the  controller.  Of  course  the  same  precau- 
tions should  be  observed  about  reversing  as  with  the  other 
controllers,  that  is,  reverse  only  in  great  emergency,  and 
then  only  to  the  first  point,  after  having  first  brought  the 
handle  to  the  off  position  and  reducing  the  speed  by  apply- 
ing the  hand  brake. 

When  there  are  two  motors  on  a  car,  an  emergency  stop 
can  be  made  when  the  trolley  is  off  or  the  fuse  is  blown  by 
reversing  to  the  highest  point.  In  shutting  off  current  on 


39 

these  controllers  be  careful  not  to  go  past  the  "off"  posi- 
tion onto  the  reverse  side  of  the  controller. 

The  early  controllers  of  the  General  Electric  Company 
have  all  been  of  the  T.  H.  rheostat  type,  as  shown  in  Fig. 
72.  It  consists  of  a  double  lever  on  each  platform  and  a 
crescent  or  half  circular  resistance  box  below  the  platform, 
over  which  a  contact  shoe  having  a  number  of  fingers  is 
made  to  slide  by  the  operating  or  controlling  handle.  The 
second  lever  has  two  positions,  a  forward  and  a  backward 
position.  It  is  the  reversing  switch  and  should  be  pushed 
to  the  extreme  end  of  its  position.  This  switch  lever  is1 
easily  distinguished  from  the  rheostat  lever  by  standing  out 
horizontally. 

To  start  the  car  the  handle  should  be  turned  from  left  to 
right,  or  (looking  down  on  it)  turned  in  the  same  direction 
as  the  hands  of  a  watch.  There  is  a  stop  at  both  extrem- 
ities, beyond  which  it  cannot  be  turned.  When  the  car  is  to 
be  stopped  the  handle  must  be  turned  backwards,  or  from 
right  to  left  once,  twice  or  more  (depending  on  the  position 
of  the  handle),  until  it  cannot  be  turned  any  farther.  It  is 
not  sufficient  that  the  contact  shoe  be  removed  from  the  re- 
sistance box,  but  the  handle  should  be  moved  until  it 
reaches  the  stop. 

In  starting,  turn  on  the  current  slowly,  moving  the  han- 
dle a  little  ways  at  a  time.  Shutting  off  the  current  should 
be  done  by  rapidly  turning  the  handle  back  to  the  "off"  po- 
sition. Reversing  is  accomplished  the  same  way  as  with 
the  series-parallel  controllers.  Never  reverse  unless  the 
current  is  first  shut  off. 

HINTS  ON   SAVING  POWER. 

It  is  not  necessary  that  a  man  be  powerful  to  control  an 
electric  car.  At  first  he  is  apt  to  spend  an  unnecessary 
amount  of  energy  at  the  brake.  Power  may  be  saved  and 


40 

the  car  would  be  subject  to  less  wear  and  tear  if  handled 
not  by  pure  strength,  but  by  proper  judgment  of  time  and 
distance.  It  should  be  considered  that  as  long  as  the  con- 
troller is  not  on  the  "off"  position  power  is  taken  into  the 
motors  and  consumed.  If  a  car  is  to  be  stopped,  turn  off 
the  power  some  time  ahead,  because  the  energy  taken  into 
the  motor  does  not  disappear  the  moment  you  shut  off  the 
current.  The  motors  and  the  car  have  weight,  and  energy 
is  stored  in  this  moving  body  and  this  energy  must  be  spent 
before  the  car  can  come  to  rest.  Some  men,  because  they 
have  not  the  right  judgment,  set  the  brake  the  moment  the 
controller  is  placed  at  the  "off"  position,  and  they  must 
then  work  hard  at  the  brake  and  consume  the  energy  still 
stored  in  the  moving  car,  by  spending  it  partly  in  wear  on 
themselves,  brake  shoes,  car  wheels,  motors  and  gears.  It 
means  a  wear  all  around,  without  a  benefit  to  anyone. 

A  test  made  by  the  author  between  a  good  and  a  poor 
motorman  with  the  same  motor  car  and  same  load,  tested 
on  the  same  dry  summer  day,  showed  that  the  better  man 
used  but  one-half  the  power  taken  by  the  other.  What  be- 
came of  the  other  energy  used  by  one  of  the  men?  You 
would  soon  know  if  you  were  frequently  around  the  barn. 
The  man  who  uses  the  most  power  seems  tired  when  he 
goes  home  in  the  evening,  from  the  hard  work  he  had  at  the 
brake.  You  Would  know  it  by  observing  the  greater  wear 
on  brake  shoes  and  constant  trouble  with  brakes,  softer  car 
wheels,  which  soon  wear  flat  in  spots,  and  frequent  loose 
bolts  on  cars  operated  by  men  of  no  experience  or  poor 
judgment.  The  simplest  thing  in  the  world  is  to  cut  off 
your  power  ahead  of  time  and  let  the  energy  stored  in  the 
car  spend  itself  by  allowing  it  to  propel  the  car  by  its  mo- 
mentum for  half  a  block  or  so,  and  you  will  be  surprised 
how  easily  it  can  be  stopped  by  setting  the  brake.  What 
has  been  said  here,  however,  is  not  always  possible  to  do, 


41 

and  a  motorman  must  use  his  judgment.  For  instance,  if 
the  pressure  or  voltage  is  low,  or  many  stops  have  to  be 
made,  or  the  motors  have  not  speed  enough  for  the  sched- 
ule time  set  by  the  company,  a  motorman  cannot  act  exact- 
ly as  he  would  wish,  but  in  these  cases  the  conditions  are 
not  normal.  Such  rules  can  be  used  as  a  guide  when  a 
road  is  properly  equipped  and  the  schedule  time  for  a  round 
trip  is  so  chosen  compared  with  the  distance  to  be  covered 
and  speed  of  the  motors  that  the  motors  can  accomplish 
their  work  easily. 

When  running  up  behind  a  team  on  the  track  and  you  see 
that  you  will  overtake  it  before  it  gets  out  of  the  way,  do 
not  crowd  your  car  up  to  speed  and  rush  up  behind  it,  as  is 
often  done,  only  to  be  obliged  to  put  the  brakes  on  hard  to 
avoid  a  collision.  You  will  make  just  as  good  time  and  save 
your  muscle  and  the  company's  power  by  letting  your  car 
run  along  slowly  enough  to  get  the  team  out  of  the  way  be- 
fore you  reach  it  instead  of  bringing  your  car  almost  to  a 
stop  after  having  run  up  to  it  at  full  speed. 

Should  the  wheels  slip  or  skid  on  going  up  grade,  bring 
your  sand  box  into  action,  and  if  the  car  wheels  continue 
to  slip  then  throw  the  controller  handle  to  the  "off"  posi- 
tion and  turn  it  on  again  step  by  step.  When  the  rail  is 
greasy  or  covered  with  snow  so  that  the  wheels  do.  not  take 
hold  of  the  rail,  apply  a  little  sand  before  starting  the  car. 
Use  the  sand  sparingly  and  be  sure  that  you  have  some 
left  when  in  need  of  it. 

SOME  PRECAUTIONS  AGAINST  ACCIDENTS. 

When  approaching  curves,  switches,  turn  outs  or  railroad 
crossings  slow  down  your  car  so  as  to  have  it  under  con- 
trol. It  is  best  to  have  the  controller  at  the  "off"  position 
and  the  right  hand  on  the  brake.  The  moment  the  wheels 
reach  the  curve,  switch  or  crossing  you  may  put  on  your 


42 

power  gradually,  to  carry  the  car  over  the  curve  or  cross- 
ing. Never  let  the  car  stop  in  a  short  curve,  such  as  is  fre- 
quently found  on  country  roads,  unless  there  are  special  in- 
structions by  the  authority  of  your  road.  When  taking 
curves  or  turn  outs  the  conductor  should  be  on  the  rear 
platform  ready  to  replace  the  trolley  should  it  jump  the 
wire.  If  the  trolley  passes  the  curve  or  switch  properly,  the 
conductor  should  ring  "go  ahead";  if  the  trolley  jumps  he 
should  ring  "stop."  If  the  conductor  has  given  his  signal 
that  the  trolley  has  jumped  off  the  wire,  the  motorman 
should  keep  his  controller  handle  at  the  "off"  position  until 
the  conductor  rings  "go  ahead." 

When  going  around  curves,  crossings  or  other  places 
where  the  car  may  jump  the  track  owing  to  roughness  of 
road-bed,  or  where  rails  are  laid  very  low  in  a  gravel  road, 
and  where  stones  may  wedge  in  the  rails,  slow  speed  should 
be  used,  as  also  when  passing  through  flooded  places  or  low 
places  where  the  rails  are  covered  with  water.  When  going 
up  grades,  it  is  best  to  put  the  controller  on  points  where 
the  resistance  is  cut  out,  and  further,  the  car  should  not  be 
stopped  or  started  on  a  grade  if  it  can  be  avoided. 

When  passing  an  overhead  insulated  switch  or  section 
insulator,  place  your  controller  always  at  the  "off"  position, 
unless  you  are  on  a  grade  or  have  other  instructions  from 
the  superintendent. 

Going  down  grade  have  your  controller  handle  at  the 
"off"  position,  the  trolley  on  the  trolley  wire  and  your 
brake  set  to  such  an  extent  that  the  wheels  turn  slowly  (not 
slide)  so  that  the  car  remains  under  your  control,  slacken- 
ing the  hold  on  the  wheels  when  the  grade  becomes  less 
steep  or  tightening  the  grip  of  the  brake  shoes  should  the 
grade  become  steeper.  Should  the  car  get  beyond  your 
control  or  the  brake  suddenly  give  out,  you  may  have  to 
resort  to  reversing  the  controller,  as  previously  explained. 


43 

It  is  a  severe  strain  on  the  motors,  t>ut  may  have  to  be 
resorted  to,  to  prevent  an  accident  or  to  save  lives.  When 
so  reversing  keep  the  controller  in  the  first  notch  should  it 
be  effective ;  if  not,  turn  the  handle  very  slowly  to  the  high- 
er notches,  as  the  fuse  is  liable  to  give  out  and  your  control 
by  means  of  current  from  the  power  house  is  gone.  Should 
the  fuse  blow  there  is  then,  as  before  mentioned,  only  one 
more  means  to  get  the  car  under  control,  and  that  is  to 
throw  the  controller  to  the  last  notch,  which  causes  the 
motors  to  act  as  dynamos.  This  plan  is  only  available 
when  there  are  two  motors  on  a  car.  The  current  is  gen- 
erated by  the  rotation  of  the  armature  in  the  field.  The 
energy  furnished  is  the  momentum  of  the  descending  car, 
which  is  out  of  your  control  and  disconnected  from  the 
power  house.  The  current  so  generated  acts  by  means  of 
the  armatures  as  a  brake  and  the  car  will  slow  up  in  the 
same  measure,  as  the  motors  generate  current.  The  means 
just  described  are  important  to  know,  but  should  never  be 
resorted  to  except  in  extreme  cases. 

When  stopping  a  car  in  the  barn  pull  down  the  trolley 
one  foot  or  a  foot  and  a  half  and  tie  it,  also  see  that  both 
controllers  are  on  the  "off"  position  and  open  the  overhead 
or  canopy  switch.  If  for  any  reason  the  trolley  should  be 
left  on  the  wire  in  the  barn  some  of  the  car  lamps  might  be 
turned  on,  which  will  be  a  warning  to  the  repair  men. 

Before  starting  see  that  the  controllers  on  both  platforms 
are  on  the  "off"  position.  Never  place  tools,  rubber  boots 
or  other  wearing  apparel,  cotton  waste  or  the  like  on  the 
side  below  the  seat  where  the  motor  cut  out  or  wire  cable 
connecting  controllers  and  motors  are  located.  Keep  this 
place  clean  and  free  from  dirt  and  moisture. 

When  examining  motors  open  your  main  or  overhead 
switch  and  take  care  not  to  let  water  drop  into  the  motor 
from  wet  clothing.  When  examining  car  motors,  fuse,  etc., 


44 

always  open  the  overhead  switch  to  avoid  shocks.  When 
operating  a  car,  any  unusual  noise  heard  should  be  located. 
Loose  bolts  should  be  reported  and  attended  to,  because  by 
the  fixing  in  proper  time  of  these  small  irregularities,  which 
are  caused  by  jarring  and  constant  operation  of  the  car, 
grave  trouble  can  be  prevented,  and  a  car  will  remain  much 
longer  in  good  repair  if  kept  so  and  watched. 

It  is  true  that  a  stitch  in  time  saves  nine.  The  writer  has 
seen  plants,  where  cars  were  neglected,  bolts  could  be 
picked  up  along  the  road,  and  on  one  occasion  a  car  was 
stalled  because  the  lower  half  of  a  field  magnet  had  dropped 
down  and  was  wedged  against  the  stone  pavement.  Should 
a  motorman  notice  irregularities  or  defects  on  the  overhead 
line  or  on  the  track  the  matter  should  be  reported. 

When  operating  on  a  road  with  steep  grades  be  sure  that 
you  are  prepared  in  damp  or  slippery  weather  to  be  able  to 
get  sand  from  the  boxes.  It1  is  not  sufficient  to  see  that 
there  is  sand  in  them,  but  that  you  know  it  is  dry  sand  and 
that  the  valve  is  in  such  condition  that  it  will  let  the  sand 
pass  through. 

Never  shift  the  reversing  handle  unless  the  controller 
handle  is  on  the  "off"  position,  nor  reverse  when  the  car  is 
in  motion  except  to  prevent  an  accident. 

When  leaving  the  platform  be  sure  your  controller  is 
turned  off  and  remove  your  controller  handle.  Keep  them 
in  your  hand  should  you  be  en  the  road,  and  in  the  barn  you 
should  leave  them,  according  to  the  rules  given  by  the  com- 
pany. The  reason  the  motorman  should  not  leave  the  con- 
troller handle  on  the  controller  is  that  accidents  are  en- 
couraged. The  author  has  frequently  seen  that  at  country 
fairs,  where  people  crowd  into  the  cars  at  both  ends,  people 
are  apt  to  strike  the  handle  with  baskets  or  coats  held  over 
the  arm,  and  can  in  this  way  start  the  car  unexpectedly. 
Keeping  the  handle  in  one's  hand  on  such  occasions  leaves 


45 

the  motorman  in  full  control  of  his  car  and  up  to  the  re- 
quirements of  his  duty  and  responsibility. 

Young  people  do  not  realize  the  responsibility  of  the  po- 
sition of  a  motorman ;  they  may  think  it  fun  to  hide  the  han- 
dle when  he  has  left  the  car  for  a  moment.  Such  liberties 
have  been  taken  by  people  who  knew  the  motorman  when 
a  car,  for  instance,  was  at  the  end  of  a  track  and  had  to  wait 
for  5  or  10  minutes.  As  the  motorman  is  held  responsible 
for  his  car  he  should  therefore  always  have  it  under  full 
control,  and  leave  it  so  no  one  can  accidentally  start  it. 

Should  at  any  time  you  feel  that  the  power  gives  out  in 
the  power  house,  for  instance,  by  the  operating  of  a  circuit 
breaker,  then  bring  your  controller  handle  to  the  "off"  posi- 
tion, close  your  lamp  circuit  and  wait  until  the  lamps  light. 

Before  starting  the  car  for  your  run,  see  that  your 
brushes  and  brush  springs  are  in  position  (unless  there  is 
some  one  else  whose  duty  it  is  to  keep  the  cars  in  readiness 
for  the  motorman).  Before  placing  the  trolley  on  the  wire, 
look  at  both  controllers  and  be  sure  that  they  are  both  at 
the  "off"  position.  Do  not  run  the  car  with  the  trolley 
pole  in  the  wrong  direction,  because  in  this  position  it  has 
no  yielding  properties  when  it  strikes  a  hanger  or  suspen- 
sion wire.  If  it  jumps  the  wire  it  would  bend  the  pole  or 
cause  trouble  to  the  overhead  wire. 

When  starting  as  a  motorman  in  a  new  town  or  on  a 
new  road  it  is  well  to  ride  once  or  twice  over  the  road  as  a 
passenger  or  with  another  motorman  in  charge  of  the  car 
to  give  you  a  chance  to  get  a  general  idea  of  the  road,  the 
location  of  switches,  turn  outs,  railway  crossings,  bridges, 
etc. 

The  operation  of  the  brakes  is  one  of  the  most  impor- 
tant duties  of  a  motorman  and  one  of  the  most  difficult. 
Accordingly,  it  is  treated  in  a  chapter  by  itself. 


CHAPTER  IV. 

OPERATION  OF  BRAKES. 

A  number  of  brake  mechanisms  are  described  in  the 
chapter  on  brakes,  Part  II,  for  the  purpose  of  learning  the 
operation.  The  description  of  the  adjustment  is  given 
more  particularly  for  those  motormen  operating  cars  on 
the  small  country  roads  where  frequently  they  are  called 
upon  to  attend  to  such  mechanical  matters.  In  large 
cities  and  on  large  roads  special  inspectors  are  provided, 
and  the  author  wishes  to  impress  especially  on  those 
motormen  who  have  inventive  faculties,  or  imagine  they 
have,  or  those  who  like  to  do  tinkering,  thaf  they  should 
touch  absolutely  nothing  about  the  car  equipment  unless 
ordered  by  the  road  officers  or  regulations  to  do  so.  The 
company  cannot  afford  to  have  a  man  experiment  with  its 
cars,  especially  when  mechanics  are  employed  to  attend 
to  all  irregularities  on  car  or  truck.  Inasmuch  as  this 
book  is  intended  to  tell  a  man  how  he  should  qualify  him- 
self for  the  position,  it  must  not  only  tell  him  how  to  get  a 
position  but  also  how  to  keep  it.  You  will  certainly  lose 
your  position  if  the  company  finds  out  that  you  tamper 
with  any  mechanical  or  electrical  part.  Playing  or  tinker- 
ing must  be  entirely  avoided  if  you  want  to  be  able  to  stay 
for  any  length  of  time  with  any  company.  However  much 
a  man  might  desire  to  fix  his  car,  it  is  not  worth  while  to 
risk  his  position  if  he  acts  against  the  rules  of  the  company 
in  doing  so. 

While  starting  your  car  from  the  barn  try  the  brakes,  to 
see  if  they  are  right.  Always  be  sure  your  brakes  are 


47 

fully  off  before  starting  your  controller.  On  grades  it  will 
be  necessary  to  start  the  controller  the  instant  the  brake  is 
released.  There  is  usually  some  slack  in  the  brake  chain 
with  hand  brakes  unless  the  shop  men  keep  them  closely 
adjusted. 

It  should  be  the  constant  effort  of  the  motorman  to 
avoid  locking  the  wheels  so  that  they  slide  or  skid  along 
the  rail.  There  are  two  good  reasons  for  this.  In  the 
first  place,  the  instant  the  wheels  begin  to  slide  on  the  rails 
the  braking  or  retarding  force  is  reduced,  or  what  is  the 
same,  the  motorman  loses  more  than  half  his  retarding 
.power.  This  has  been  fully  proved  by  experiment  and  by 
experience.  In  the  second  place,  there  is  danger  that  by 
this  sliding  along  the  rails  a  flat  place  will  be  worn  on  the 
wheels.  Such  flat  places  will  pound  with  every  turn  of  the 
wheels  and  rapidly  grow  worse,  so  that  the  noise  becomes 
unbearable  to  the  public  and  the  wheels  must  be  turned 
down  at  considerable  expense  or  thrown  away.  A  flat 
wheel  on  a  car  is,  therefore,  no  credit  to  a  motorman, 
and  on  some  roads  the  penalty  for  a  flat  wheel  is  suspen- 
sion. It  is  often  hard  to  avoid  sliding  the  wheels  when 
sleet  or  mud  is  on  the  rails,  but  this  should  be  remembered 
above  all,  viz.,  never  turn  on  sand  after  the  wheels  have 
commenced  to  slide  without  first  letting  up  on  the  brakes 
so  that  the  wheels  can  turn.  The  safer  plan  when  stop- 
ping on  a  slippery  rail  is  to  apply  sand  at  the  same  time 
you  apply  the  brakes.  Remember  that  you  cannot  stop  as 
quick  by  sliding  the  wheels  as  you  can  by  putting  on 
brakes  firmly  without  sliding  them.  In  coming  to  a  steep 
down  grade  be  sure  to  slow  up  your  car  before  reaching 
the  incline  and  set  your  brakes  gradually.  If  the  wheels 
get  to  sliding  on  the  grade  loosen  up  on  the  brakes  until 
they  begin  to  turn  again.  Cars  have  run  away  down  hills 


48 

because  motormen  have  lost  their  heads  or  failed  to  know 
and  remember  this  point. 

The  wear  or  lasting  qualities  of  the  brake  shoes  and  the 
power  taken  from  the  power  plant  by  a  motorman  to  run  a 
car  depends  to  a  considerable  extent  on  his  proper  judg- 
ment of  time  and  distance.  The  less  he  absorbs  the  stored 
energy  with  the  brake,  the  smaller  will  be  the  wear  on 
brake  shoes  and  car  wheels  and  the  smaller  the  power 
taken. 

It  is  not  a  good  plan  to  make  gradual  stops  by  applying 
the  brakes  lightly  a  long  distance  back  of  where  you  want 
to  stop,  as  you  lose  time  in  getting  over  the  road  in  this 
way  and  require  more  power  in  making  up  for  it.  Let  the 
car  drift  with  brake  entirely  off  until  a  short  distance  from 
the  stopping  place,  and  then  apply  them  hard  enough  to 
make  a  comparatively  short  stop  without  sliding  the  wheels 
or  making  it  uncomfortable  for  the  passengers. 


CHAPTER  V. 

HOW  TO    REMEDY   TROUBLES. 

On  many  large  roads  the  motormen  are  expected  to  do 
nothing  beyond  operating  their  cars,  and  whenever  trouble 
occurs  to  a  car  on  the  road  it  is  pushed  in  by  the  next  and 
the  repair  men  at  the  barn  attend  to  the  repairing.  A 
motorman  should  of  course  always  abide  by  the  rules  of 
his  company,  and  if  they  forbid  the  opening  of  motors  or 
controllers  by  motormen  the  author  does  not  mean  these 
instructions  to  in  any  way  interfere  with  rules  which  may| 
seem  necessary  to  the  officers  of  large  systems  where  the 
motormen  are  not  all  well  posted  and  where  inspectors  are 
employed  whose  special  work  it  is  to  remedy  slight  troubles 
and  where  mischief  may  be  done  by  the  tampering  of  those 
who  do  not  understand  the  apparatus.  Nevertheless,  there 
are  many  small  roads  where  a  knowledge  of  how  to  remedy 
troubles  is  needed,  and  even  on  the  large  roads  mentioned 
the  man  who  understands  his  car  can  save  many  delays  and 
knows  how  to  report  troubles  intelligently. 

In  enumerating  many  of  the  troubles  to  which  the  cars 
and  motors  are  subject  and  giving  instructions  for  their 
temporary  remedy,  the  author  wishes  to  place  in  the  hands 
of  the  motorman  facts  and  means  which  are  helpful  for 
such  an  occasion.  However,  no  one  should  think  that 
without  practical  experience,  by  simply  reading  these  lines, 
that  he  can  manage  a  car  as  well  as  a  man  who  has  been 
operating  one  for  years.  Practical  experience  is  abso- 


50     • 

lutely  necessary,  but  in  connection  with  it  this  chapter  will 
be  very  helpful  to  the  motorman. 

A  great  deal  must  be  learned  by  actual  experience,  and 
success  in  economical  operation  on  a  car  line  depends 
partly  on  the  watchfulness  of  the  motorman.  While  oper- 
ating his  controller  he  can  readily  detect  irregularities, 
first,  by  the  way  the  motors  take  the  current  when  the  con- 
troller is  operated,  and  secondly,  when  the  car  is  under 
way,  by  the  sound  of  the  motors. 

The  economy  which  can  thus  be  accomplished  lies  in  the 
fact  that  loose  bolts,  a  loose  connection  and  the  like  are 
easily  tightened.  These  are  small  troubles  caused  by  con- 
stant jarring  of  the  car,  which  are  easily  attended  to. 
However,  if  the  car  is  not  watched  bolts  will  be  lost,  bear- 
ings will  come  loose,  the  armature  revolving  at  a  great 
rate  of  speed  may  be  rubbing  against  the  field  magnet 
poles,  or  a  wire  working  out  of  its  connection  may  cause 
a  short  circuit  and  blow  the  fuse,  etc.  It  will  be  readily 
seen  that  these  small  troubles,  if  not  attended  to  in  time, 
are  the  causes  of  others  far  more  serious,  yet  a  turn  of  the 
wrench  or  the  screwdriver  in  proper  tirne  may  easily  pre- 
vent such  troubles  on  the  road.  The  golden  rule,  "a  stitch 
in  time  saves  nine,"  should  be  remembered  at  all  times, 
and  besides  this  one,  "cleanliness  is  next  to  Godliness." 
Keep  your  motors,  connections  and  contact  terminals  clean 
and  dry.  Before  working  around  the  electrical  apparatus 
pull  off  trolley  and  open  overhead  switch. 

If  the  car  fails  to  start  when  the  controller  is  "on"  and 
both  overhead  switches  are  closed,  the  trouble  is  due  to  an 
open  circuit,  and  probably  to  one  of  the  following  causes : 

i.  The  fuse  may  have  blown  or  melted.  Open  an  over- 
head switch  or  pull  off  the  trolley  and  put  in  a  new  fuse, 
removing  the  burned  ends  from  under  the  binding  posts 
before  doing  so.  Never  put  in  a  heavier  fuse  than  that 


51 

specified  by  the  company,  as  it  might  result  in  damage  to 
the  equipment  by  allowing  too  large  a  current  to  flow. 
The  fuse  may  blow  because  of  some  trouble  on  the  car,  as 
will  be  explained  a  little  further  on. 

2.  On  a  dry  summer  day,  when  there  is  much  fine  dust 
on  the  track,  it  happens  that  the  car  wheels  do  not  make 
proper  contact  with  the  rail  and  the  car  fails  to  start.     In 
such  a  case  try  to  establish  contact  by  rocking  the  car 
body.     Should  this  fail  to  work,  the  conductor  should  take 
the  switch  bar  or  a  piece  of  wire  and,  holding  one  end 
firmly  on  a  clean  place  on  the  rail,  hold  the  other  against 
the  wheel  or  truck.     This  will  make  temporary  connection 
until  the  car  has  started.     The  conductor  should  be  sure 
to  make  his  rail  contact  first  and  keep  it  firm  during  this 
operation  or  he  may  receive  a  shock. 

3.  If  the  track  conditions  are  apparently  good,  it  may 
be  that  the  car  stands  on  a  piece  of  dead  rail — a  piece  of 
rail  on  which  the  bonding  has  become  destroyed.     In  that 
case  the  car  conductor  would  have  to  go  to  the  next  rail 
section  with  a  piece  of  wire  to  connect  the  two  rails  and 
then  order  the  motorman  to  start  his  car. 

4.  Another  outside  trouble  which  the  author  has  no- 
ticed, especially  on  cars  having  wooden  trolley  poles,  is 
that,  due  to  the  constantly  varying  pressure  on  the  pole, 
the  wire  connecting  the  trolley  wheel  with  the  trolley  base 
breaks  off  short  near  the  place  where  the  trolley  head  or 
fork  is  mounted.    In  such  a  case  wrap  a  bare  piece  of  wire 
around  the  lower  part  of  the  trolley  fork  and  continue  it 
around  the  wooden  pole,  and  be  sure  to  establish  good 
connection  between  the  wire  you  place  temporarily  round 
the  pole  and  that  one  running  down  to  the  trolley  base. 
This  latter  irregularity,  can  be  noticed  by  the  motorman, 
because  the  current  taken  into  the  car  is  irregular.     Some- 
times the  motors  get  the  power  properly ;  at  other  times 


52 

they  start  slowly  as  if  they  did  not  receive  the  proper  cur- 
rent. In  the  evening  it  can  be  noticed  by  the  slight  arc- 
ing that  takes  place  between  the  broken  ends. 

5.  A  brush  or  two  may  not  have  been  placed,  or  if 
placed,  may  fit  too  tightly  in  the  brush  holder,  so  that  the 
springs  do  not  establish  contact  between  brush  and  com- 
mutator.    If  this  is  the  case,  remove  brushes  and  sand- 
paper them  until  they  go  into  the  brush  holder  easily. 

6.  The  contact  fingers  on  a  controller  are  rough,  burnt, 
and  perhaps  bent  so  that  the  drum  cannot  make  contact. 
Try  to  remove  burnt  surface    with    sandpaper  and  bend 
fingers  or  contacts  into  their  proper  position.     Should  this 
fail,  then  operate  the  car  with  the  other  controller.     In  this 
case  the  conductor  should  be  on  the  front  platform  to 
handle  the  brake  and  give  orders  to  the  motorman  when 
to  start  and  stop,  as  the  occasion  requires.     Under  these 
conditions  the  car  should  never  be  allowed  to  travel  at  a 
high  speed.     It  may  also  be  due  to  wear  on  both  the  con- 
tact surfaces  of  the  drum  and  the  finger,  which  may  have 
been  burnt  and  worn  away  to  such  an  extent  that  contact 
is  not  established  when  the  controller  handle  is  placed  on 
the  first  notch. 

7.  A  loose  or  broken  cable  connection.     This  can  be 
located  and  placed  and  fastened  in  its  position.     It  is,  in 
most  instances,  a  cable  connected  to  one  of  the  motors, 
rheostat,  or  lightning  arrester  and  very  seldom  in  the  con- 
troller stand. 

8.  A  burnt  rheostat.     A  rheostat  may  have  received 
too  great  a  current  for  some  time  and  the  first  contact 
terminal  may  be  broken.     In  such  a  case,  if  temporary 
connection  cannot  conveniently  be  established,  the  car  will 
not  start  at  the  first  notch,  but  at  the  second  it  will  start 
with  a  jerk. 

9-     If  car  refuses  to  start  on  the  first  contact,  but  starts 


53 

all  right  on  the  second  and  acts  normal  thereafter,  then  there 
is  an  open  circuit  in  the  rheostat,  either  internally,  or  the 
first  cable  connection  is  broken.  It  may  also  be  due  to  a 
worn  controller  and  the  contacts  may  be  blistered  or  burnt. 
Move  the  controller  handle  slightly  beyond  the  notch  or  go 
direct  to  the  second  notch. 

10.  The  field  coil  of  a  motor  may  be  grounded  so  that  the 
fuse  blows  whenever  current  is  turned  on.     Cut  out  the 
faulty  motor,  as  explained  in  Chapter  III;  Part  II. 

11.  Armature  or  commutator  grounded.    Cut  out  motor 
as  in  10. 

12.  Lightning  arrester  is  grounded  by  dirt  between  the 
discharge  points.     Remove  the  dirt,  as  the  fuse  will  blow 
as  long  as  the  trouble  exists.     Should  this  not  be  possible 
then  disconnect  the  lightning  arrester,  ground  wire,  insert 
fuse  and  go  ahead.    The  trouble  lies  in  the  arrester. 

13.  The  car  starts  and  the  fuse  may  blow.    This  may  be 
due  to  a  heavy  load  and  the  fuse  not  securely  fastened  to 
its  terminals.    The  screws  holding  the  terminals  of  the  fuse 
should  be  tight,  because  loose  contact  at  these  points  will 
cause  heating  and   an   increased   resistance,   and   in   conse- 
quence a  quicker  burning  of  the  fuse. 

14.  Case  13  may  happen  with  comparatively  few.  pas- 
sengers.   The  load  may  be  caused  artificially  by  having  the 
brakes  partially  set  or  dirt  clogging  between  the  brake  shoes 
and  car  wheels.     Remove  obstruction  between  brake  shoes, 
then  insert  fuse. 

15.  In  car  equipments,  with  motors  permanently  in  par- 
allel, fuse  will  blow  if  a  field  or  armature  is  short  circuited. 
Proceed  as  in  10. 

There  are  also  other  irregularities  which  may  occur,  as 
follows : 

1 6.  Some  cables  form  a  short  circuit  either  under  the 
seat  or  below  controller  due  to  dampness,  dirt,  damaged 


54 

insulation,  etc.  This  can  readily  be  detected  by  the  smell 
of  burnt  rubber.  Having  found  the  place,  first  open  your 
overhead  switch,  then  proceed  to  wrap  rubber  tape  around 
the  bare  place.  If  this  is  not  on  hand,  use  some  dry  cotton 
or  woolen  rag  torn  into  a  narrow  band  or  else  dry  string. 
If  the  wires  cannot  be  separated  far  enough,  place  some 
short  pieces  of  dry  wood  between  them  and  then  tie  them 
together. 

17.  The  car  starts  and  after  the  controller  reaches  a  cer- 
tain point  fuse  blows.    One  armature  or  a  field  is  short  cir- 
cuited.   Cut  out  the  faulty  motor  and  go  on  with  the  other. 

1 8.  The  car  starts,  stops  and  starts  again.     This  may 
be  caused  by  a  loose  contact  finger  at  the  controller  or  by 
a  loose  cable  or  wire.     Remove  casing  from  controller,  and 
if  you  see  blisters  on  the  drum  of  your  controller  examine 
the  finger  belonging  to  this  particular  contact,  clean  it  and 
screw  it  home  or  bring  it  back  to  its  normal  form  should  it 
have  been  bent.    If  the  controller  looks  all  right  the  trouble 
may  be  found  to  be  due  to  a  loose  cable  connected  to  the 
terminals  of  a  motor.     Take  screwdriver  and  tighten  all 
cables  going  to  the  field  coils,  armature  and  brush  holders. 
Also  examine  brushes.     If  your  commutator  looks   dark 
and  burnt  it  may  be  due  to  a  brush,  which  has  worn  down 
to  such  an  extent  that  the  brush  springs  do  not  press  it 
against  the  commutator.     In  this  latter  case   substitute  a 
new  brush,  but  if  none  is  at  hand,  cut  out  the  motor  and 
go  ahead  with  the  other. 

19.  The   car   starts   with   a   jerk,   but   afterward   runs 
smooth  and  normal.     There  is  a  short  circuit  probably  in 
the  rheostat.     Examine    the    rheostat    terminals    and   re- 
move the  trouble,  which  may  be  due  to  the  crossing  of  the 
cables  or  a  loose  cable  touching  another  terminal.     Should 
the  trouble  be  internal,  namely,  inside  of  the  rheostat,  you 


55 

should  not  touch  it  at  all,  but  run  your  .car  back  to  the 
barns  and  report  the  defects. 

20.  A  motor  field  or  armature  coil  may  be  burned  out. 
Cut  out  this  motor,  which  can  be  detected  by  the  smell  of 
shellac  and  burnt  cotton. 

21.  Should  the  speed  of  the  motor  increase  beyond  nor- 
mal, a  field  magnet  coil  is  either  short  circuited  or  burnt 
out.     The  motor  should  be  cut  out. 

22.  Should  there  be  heavy  flashing  in  the  controller  and 
smoking,  it  is  due  to  dirt,  moisture,  metal  dust  in  the  con- 
troller,  or  too  slow  turning  off  of  the   controller.     Open 
your  overhead  switch  and  blow  out  the  dust  from  the  ring 
terminals,  remove  also  all  dust  at  the  lower  ends  of  the 
controller  and  see  that  it  is  dry. 

23.  Should  the  lamps  not  light  up  on  turning  the  lamp 
switch,  see  if  your  lamp  circuit  fuse  is  not  burnt.     If  in 
good   order  either  a   lamp  is   not  screwed   home   into  its 
sockets  or  one  of  the  lamps  is  burnt  out.     If  one  is  burnt 
out  none  will  light  up,  because  they  are  in  series. 

There  are  also  other  irregularities  which  may  occur  which 
it  is  well  for  the  motorman  to  understand,  although  he  may 
not  be  able  to  remedy  them. 

24.  One  motor  of  a  car  becomes  a  great  deal  hotter  than 
the  other.    This  may  be  due  to  uneven  distribution  of  work 
caused  by  difference  in  the  magnetic    circuit    of  the  two 
motors,  or  to  one  set  of  wheels  being  smaller  in  diameter 
than  the  other,  or  a  ground  in  the  field  coil  or  short  circuit 
in  the  field  coil  of  the  hot  motor. 

25.  Abnormal  heating  of  one  of  the  motor  armatures 
may  be  due  to  its  striking  the  field  poles  when  rotating. 

26.  Heating*  of  the  motor  may  also  be  due  to  defective 
brake,  caused  by  weak  release  springs  or  too  short  a  brake 
chain. 


56 

27.  Heating  may  be  also  due  to  the  oil  or  grease  used 
which  does  not  melt  properly,  if  at  all.    A  full  grease  or  oil 
cup  is  no  sign  of  proper  lubrication.     If  it  is  found  that 
bearings  heat,  in  spite  of  full  grease  cups,  take  a  clean  stick, 
make  a  hole  through  the  grease  down  to  the  shaft,  pour  in 
soft  oil  and  go  ahead.     It  may  not  be  a  bad  idea  to  oc- 
casionally feel  the  car  axle  bearings,  which  get  pretty  warm 
when  insufficiently  supplied  with  oil. 

28.  A  sharp,  rattling  noise  when  the  car  is  traveling  at 
high  speed  is  the  consequence  of  an  ^uneven  commutator. 
A  commutator  that  is  flat  in  places,  or  a  few  bars  that  have 
become  loose  and  project  slightly,  cause  the  brushes  to  be 
quickly  forced  away  from  the  commutator  by  the  high  bars, 
and  to  be  forced  back  onto  the  lower  ones  by  the  brush 
holder  spring  as  soon  as  a  high  bar  has  passed.    The  rapid 
succession  of  these  changes  causes  the  noise,  which  should 
be  reported.     It  causes  heavy  sparking  at  the  brushes  and 
excessive  heating!  of  the    commutator    segments,    besides 
rapid  wearing  down  of  the  brushes.    This  can  be  remedied 
only  in  the  repair  shop. 

29.  A  dull  thumping  noise,  also  connected  with  spark- 
ing at  the  brushes,  may  be  due  to  the  armature  striking  or 
rubbing  against  the  pole  pieces.    If  this  is  due  to  loose  bear- 
ings the  cap  bolts  ^should  be  tightened,  but  if  on  account 
of  wornout  boxes,  the  car  should  be  taken  to  the  barn  at  a 
slow  rate  of  speed,  and  reported  without  delay. 

30.  If  the  car  starts  with  a  jerk  and  the  gears  make 
considerable  noise,  the  teeth  of  the  pinion  may  be  worn  or 
fit  loosely  in  the  gear,  or  the  key  seat  on  the  armature  shaft 
has  been  made  wider  by  the  constant  wear  of  a  loose  key. 
This  trouble  should  be  reported  as  soon  as  p'ossible. 

31.  Loud  noise  from  the  gearing  is  sometimes  due  to 
loose  gears,  the  teeth  of  which  have  too  much  play.     It  is 
increased  if  the  gear  casing  is  partially  opened,  caused  by 


57 

loose  bolts,  or  when  they  are  removed  entirely.  The  same 
trouble  of  improper  meshing  of  teeth  in  the  gears  may  be 
due  to  a  bent  armature  shaft  or  a  bent  car  axle.  The  trouble 
should  be  reported  to  the  car  inspector  or  other  proper 
authority. 

32.  Another  noise  frequently  heard  is  the  thumping  of 
a  car  wheel  which  has  a  flat  spot.    The  trouble  may  be  due 
to  natural  wear,  or  due  to  poor  track,  but  most  frequently 
due  to  improper  handling  of  the  brake,   which  is  set  too 
suddenly  and   prevents  the  wheels   from  turning.     If  the 
brake  is  set  too  tight  when  going  down  grade,  it  will  cause 
the  wheels  to  slide  along  the  rails  on  four  points,  which, 
due  to  friction,  become  heated,  with  the  result  of  softening 
that  part  of  the  wheel,  which  will  wear  rapidly  into  a  flat 
place,   causing   a    disagreeable   hammering   noise   at   every 
revolution  of  the  wheel. 

33.  If  the  motors   start  with  a    jerk    or    do    not  run 
smoothly,  the  conductor  should  lift  one  of  the  trap  doors 
at  a  time,  while  the  car  is  running,  to  examine  the  com- 
mutator and  brushes  of  each  motor.     Should  there  be  seen 
a  flash    all  around    the    commutator    or    connecting    two 
brushes,  then  there  is  an  open  circuit  in  the  armature.    Cut 
out  the  motor  and  proceed  on  your  trip  with  the  other  motor 
alone. 

A  short  circuit  on  a  motor  in  a  car  means  that  by  some 
cause  or  defect  a  shorter  circuit  is  found  by  the  electric  cur- 
rent other  than  is  properly  provided  in  the  system,  and  it 
has  the  effect  of  weakening  or  disabling  the  part  thus 
affected.  For  instance,  assume  that  to  make  the  magnet 
of  a  motor  strong,  there  is  placed  around  it  500  turns  of 
wire;  due  to  dampness  or  dirt,  let  there  be  cut  out  300  or 
400  turns ;  then  a  current  will  flow  through  but  100  turns ; 
the  circuit  has  become  shorter  than  was  intended  by  the 
designer.  Such  defects  not  only  lead  to  irregularity  in 


58 

handling,  but  cause  a  strain  on  the  dynamo  in  the  power 
house.  Every  second  that  a  motor  runs  after  something 
is  wrong  is  liable  to  greatly  increase  the  damage.  There- 
fore, cut  out  a  defective  motor  the  moment  it  is  discovered. 
Short  circuits  can  be  caused  by  dirt  and  rain,  by  crossing  of 
the  flexible  wires  joined  to  the  motors  and  in  many  other 
ways.  A  short  circuit  on  a  line  means  that  nearly  all  or  all 
the  necessary  resistance  which  a  motor  or  other  translating 
device  should  offer  when  in  good  condition  has  been  re- 
moved by  a  defect,  and  now  acts  as  a  conductor  of  very 
little  resistance  connecting  the  two  wires  constituting  the 
line.  In  a  railway  system  this  would  mean  a  direct  connec- 
tion between  trolley  wire  and  rail,  the  current  not  properly 
passing  through  the  motors. 

A  ground  on  a  motor,  or  a  short  circuit,  means  that  some 
part  of  the  insulation  has  become  defective  and  that  the 
current  has  found  its  way  to  the  iron  core.  In  most  rail- 
way systems  used  at  present  the  trolley  wire  is  one  of  the 
conductors,  while  the  rails  form  the  second  or  return  con- 
ductor. A  ground  on  a  motor  equipment  indicates  that  a 
part  of,  the  field  or  the  armature  winding,  through  which  the 
current  should  flow  before  reaching  the  car  wheel,  has  been 
cut  out  of  action  by  a  defect.  The  car  will  then  not 
operate  as  well,  and  depending  on  the  seriousness  of  the 
defect,  will  go  slower  or  faster  than  when  in  good  order. 
If  a  ground  cuts  out  a  great  deal  of  the  motor  circuit  it  is 
about  equivalent  to  a  short  circuit.  If  a  guard  wire,  tele- 
graph or  telephone  wire  should  fall  over  the  trolley  wire 
and  touch  the  ground  it  would  establish  an  earth  connec- 
tion, which  is  equivalent  to  a  short  circuit  on  the  dynamo. 

Should  a  wire  be  found  hanging  over  the  trolley  wire,  but 
not  reaching  the  ground,  it  should  be  removed  with  the 
greatest  of  care.  It  does  not  form  a  ground,  as  it  may  be 
several  feet  away  from  the  ground ;  however,  it  is  charged 


59 

by  touching  the  trolley  wire.  In  trying  to  remove  it  with 
the  bare  hands,  standing  on  the  ground,  the  man  who  in- 
tends to  give  his  services  to  remove  the  obstruction  forms 
himself  the  rest  of  the  circuit  and  establishes  a  ground 
through  his  body.  The  moment  he  would  touch  this  ap- 
parently lifeless  wire  with  his  bare  hands,  the  current  dis- 
charges through  his  body  into  the  ground. 

A  wire  covered  with  rubber  insulation  can  be  handled, 
but  even  in  this  case  the  same  precaution  should  be  taken, 
as  no  one  can  tell  how'  good  the  insulation  may  be.  Fre- 
quently rubber  insulation  becomes  brittle  and  hard  when 
exposed  to  atmospheric  changes — hot  and  cold  weather, 
rain  and  snow — and  in  this  state  the  insulation  is  worse 
than  none,  because  persons  may  think  the  covering  still  to 
be  an  insulator  when,  in  fact,  it  may  be  carbonized  and 
itself  a  partial  conductor.  In  damp  weather  and  with  high 
voltages,  as  now  commonly  used,  such  insulation  should 
not  be  relied  on  and  should  be  treated  as  if  the  wire  was  a 
bare  one. 

If  you  see  the  construction  man  on  his  tower  wagon 
handle  the  trolley  wire  with  bare  hands,  you  should  re- 
member that  he  stands  on  a  high  wooden  ladder,  and  he 
therefore  is  well  insulated  from  the  ground.  Even  in  his 
lofty  position  he  has  to  be  on  his  guard,  because  the  trolley 
suspension  wires  are  in  some  cities  connected  to  the  iron 
poles  without  an  insulator  between  them,  only  one  insu- 
lator being  provided,  which  is  interposed  between  the  trol- 
ley wire  and  the  span.  If  he  touches  either  one  alone  he 
is  safe,  but  if  he  touches  the  trolley  wire  and  at  the  same 
time  this  span  wire  attached  to  the  iron  pole,  he  establishes 
a  connection  from  the  trolley  to  the  ground  through  his 
hands,  arms  and  body  and  has  to  suffer  the  consequences. 
In  most  towns  the  trolley  suspension  wires  are  now  insu- 


60 

lated  at  both  ends,  so  that  they  can  be  handled   without 
danger. 

It  may  happen  that  you  have  to  handle  a  live  trolley  wire 
which  has  broken  or  fallen  in  the  street,  or  a  telephone  or 
other  wire  which  has  fallen  across  the  trolley  wire.  Never 
take  hold  of  the  wire  with  your  bare  hands.  If  you  must 
take  hold  of  it,  put  several  thicknesses  of  clothing  between 
your  hands  and  it,  if  the  cloth  is  dry.  Otherwise,  use  sticks 
and  a  rope  to  remove  it. 


Part  II. 


CHAPTER  1. 

THE  PRINCIPLES  OF  THE  ELECTRIC  MOTOR. 

Many  persons  have  the  idea  that  a  dynamo  or  an  electric 
motor  is  so  complicated  a  device  that  it  takes  years  of 
study  to  understand  it.  Nothing  is  farther  from  the  truth. 
The  fact  is,  that  it  is  built  on  one  of  the  simplest  principles, 
and  if  this  principle  is  well  understood  it  will  be  easy  to 
understand  any  machine,  because  in  analyzing  we  always 
go  back  to  the  simple  principle  and  leave  out  the  many 
complicated  additions  which  may  be  attached  to  a  machine 
for  one  reason  or  another. 

A  dynamo  or  motor  is  nothing  else  but  a  powerful  mag- 


FIG.  28.  FIG.  31. 

net,  and  differs  in  principle  but  slightly  from  the  common 
horseshoe  magnet.  Fig.  28  represents  a  magnet  which  we 
can  buy  in  any  hardware  store.  To  understand  the  action 
of  a  dynamo  or  motor,  it  becomes  necessary  to  understand 
this  little  magnet.  It  is  a  piece  of  flat  steel  bent  into  the 
form  of  a  horseshoe,  which  is  hardened  and  afterward  mag- 
netized. It  has  been  found  that  steel,  when  hardened,  will 
retain  magnetism  for  a  long  time,  that  is,  for  months  and 


64 

years ;  provided,  however,  that  it  has  constantly  some  work 
to  do.  For  this  reason  the  keeper  B  is  always  found  with 
the  magnet.  The  keeper  or  armature  B  is  a  simple  piece 
of  soft  iron  which,  when  brought  near  to  the  end  of  the 
magnet  poles  or  the  horseshoe,  will  be  attracted  and  held 


^If* 


FIG.  29.  FIG.  30. 

by  the  magnet.  If  we  attempt  to  remove  this  piece  of  iron 
B  from  magnet  A  we  find  that  it  requires  some  force ;  that 
it  takes  energy  to  pull  off  the  iron  piece  from  the  magnet. 
We  are  therefore  confronted  by  the  fact  that  this  bent  piece 
of  steel  has  energy  stored  in  it,  and  that  this  energy  is 
capable  of  doing  work.  The  magnet,  which  at  first  had  to 
be  charged,  takes  up  energy  which  is  stored  in  it,  and 
which  afterward  it  can  return  to  do  useful  work.  It  is 
similar  to  a  spiral  spring.  We  have  to  spend  energy  to 
compress  it  (Fig.  29),  but  the  moment  we  reduce  the  pres- 
sure we  feel  that  the  spring  tries  to  utilize  the  stored  energy 
and  force  our  fingers  apart  (Fig.  30). 

If  we  remove  the  armature  from  the  horseshoe  magnet, 
the  energy  acts  from  one  end  of  the  magnet  to  the  other 
through  the  air.  The  energy  or  flow  of  energy  is  not  visible 
to  the  eye,  but  the  results  of  this  force  are  made  visible  by 
the  action  of  iron  filings  when  brought  near  to  a  magnet. 
With  the  aid  of  iron  filings  it  is  found  that  this  force  is  very 
intense  near  and  between  the  ends  of  poles,  and  spread  in 
curves  the  farther  we  go  out  into  the  space  surrounding 
the  magnet  poles.  Fig  31  gives  a  clear  view  of  some  of 


65 

these  lines.  The  spots  which  are  marked  N,  S,  are  the 
places  where  the  paper  touches  the  ends  or  poles  of  the 
magnet,  which  is  beneath  the  sheet  of  paper  presenting  the 
figure. 

The  iron  filings,  which  are  thrown  on  top  of  the  sheet, 
arrange  themselves  in  lines  as  seen.  Between  the  poles 
these  lines  appear  straight,  and  become  more  and  more 
curved  the  longer  the  path  becomes  from  one  pole  to  the 
other.  It  must,  however,  be  borne  in  mind  that  the  sheet 
is  but  a  single  plane  through  the  sphere  or  globe  surround- 
ing the  magnet,  and  that  the  power  of  activity  goes  in  all 
directions  surrounding  the  poles,  as  the  branches  and 
leaves  surround  the  trunk  of  a  tree.  These  same  curves  of 
activity  can  be  seen  to  go  in  all  directions  in  space  by  tak- 
ing a  small  compass  needle  and  passing  it  from  one  pole 
to  the  other.  The  needle  will  during  its  travel  change  its 
position  with  relation  to  the  two  poles,  and  will  always  take 
such  a  position  that  its  two  ends  lie  in  line  with  the  par- 
ticular curve  which  unites  it  with  the  two  poles  (Fig.  32). 
It  is  owing  to  this  custom  of  representing  this  force  by  the 


curved  lines  that  it  became  usual  to  speak  of  "magnetic 
lines  of  force,"  which,  however,  should  not  be  considered 
as  actual  lines,  nor  that  they  simply  connect  the  two  poles, 
as  in  Figs.  24  and  25,  but  as  a  force  which  threads  through 
the  whole  length  of  the  magnet,  as  shown  in  Fig.  33.  This 
energy  is  not  only  vested  in  the  extremities  or  poles,  but 


66 

is  the  sum  of  the  forces  of  all  the  particles  of  steel  consti- 
tuting the  magnet.  The  energy  is  in  the  magnet,  but  its 
manifestations  become  apparent  most  strongly  at  the  points 
where  it  passes  from  the  magnetic  medium  to  a  non- 
magnetic one.  Air  is  non-magnetic,  while  iron  and  steel 


are  strongly  magnetic  substances.  Owing  to  the  great 
preference  that  the  magnetism  has  for  iron,  it  selects  the 
path  indicated  in  Fig  33,  rather  than  to  go  straight  from 
the  pole  N  to  the  S  pole  through  the  air.  In  passing 
through  the  iron  the  lines  of  magnetic  force  cause  the 
armature  or  keeper  to  also  become  a  magnet.  The  poles 
are  marked  S  and  N  as  abbreviations  for  "South"  and 
"North,"  because  they  correspond  to  the  poles  or  ends  of 
the  magnetic  needle  of  a  compass.  The  keeper  becomes  a 
magnet  under  the  influence  of  the  horseshoe  magnet. 

If  we  substitute  for  the  keeper  a  permanent  magnet,  viz., 
a  piece  of  steel  in  which  the  poles  are  fixed,  we  find  that  if 
the  two  magnets  are  faced  N  to  S  and  S  to  N,  as  in  this 
figure,  they  will  attract  each  other.  If  placed  so  that  the 
two  N  poles  are  together  and  the  two  S  poles  are  together, 
no  attraction  will  take  place,  but,  on  the  contrary,  they  will 
repel  each  other,  and  from  this  fact  comes  the  rule  "like 
poles  N,  N,  or  S,  S,  repel  each  other,  unlike  poles  attract 
each  other." 


67 

A  great  step  in  advance  was  made  when  the  following 
fact  was  discovered :  It  was  found  that  if  a  wire  carrying 
an  electric  current  and  a  magnetic  needle,  delicately  sus- 
pended, were  brought  close  to  each  other,  that  the  needle 
was  deflected  to  one  side.  If  the  current  flowed  in  a  wire 
above  the  needle  in  the  direction  from  south  to  north, 
namely,  if  the  wire  itself  was  held  in  a  direction  due  north 
and  south  above  the  needle,  and  the  current  flowed  north 
through  the  wire,  then  the  north-seeking  end  of  the  needle 
was  deflected  to  the  west.  If  the  wire  was  held  above  the 
needle,  but  turned  round  so  that  the  current  flowed  from 
north  to  south,  then  the  north-seeking  point  of  the  needle 
was  deflected  to  the  east.  Lastly,  if  the  wire  was  held 
below  the  needle,  the  direction  of  the  deflection  was  re- 
versed. It  was  clear,  then,  what  had  been  long  suspected, 
that  there  was  some  connection  between  magnetism  and 
electricty. 

This  experiment  also  showed  that  the  electric  current 
could  act  through  space,  and  acts  on  the  magnetic  needle 
just  as  the  horseshoe  magnet  would.  If  that  is  the  case 


then  it  must  disturb  the  space  surrounding  it  while  a  cur- 
rent is  flowing;  it  must  establish  a  sphere  around  itself  of 
the  nature  of  a  magnet,  a  sphere  that  has  magnetic  proper- 
ties. Investigating  the  space  around  the  wire  with  iron 
filings,  we  find  a  grouping  of  the  little  iron  particles  (Fig?. 
34  and  35),  and  that  the  wire  carrying  a  current  attracts 


68 


iron  filings.     Fig  35  shows  a  picture  of  the  force  around 
the  wire,  while  Fig.  34  shows  an  end  view  of  Fig.  35. 

Fig.  36  represents  a  magnetic  needle  surrounded  by  a 
coil  of  wire  carrying  a  current.  It  appears  that  we  have 
here  the  principle  of  an  electric  motor  with  this  one  differ- 
ence, that  owing  to  the  arrangement  of  parts  the  move- 
ment is  not  rotary.  Motion  is  imparted,  but  not  contin- 
uous motion,  in  one  direction.  It  was  found  further  that 
if  we  take  a  spool  of  wire  (Fig.  37)  without  any  iron  near 
it  and  send  an  electric  current  through  it,  as,  for  instance, 
from  a  battery  B,  through  the  coil  A,  that  it  behaved  just 


as  a  magnet  would,  viz.,  that  it  exhibited  a  north  pole  at 
one  extremity  and  a  south  pole  at  the  other,  and  that  it 
attracted  one  end  of  the  magnetic  needle  at  one  end  and 
the  other  at  the  opposite  end;  just  what  we  know  would 
take  place  if  we  had  an  ordinary  straight  magnet  or  bar 
magnet  instead  of  the  spool  with  the  current  flowing 
through  it. 

Lastly,  one  more  phenomenon  must  be  mentioned,  which 
will  complete  our  picture.  If  we  take  a  spool  of  wire 
A  (Fig.  38)  and  connect  it  to  another  coil  B  several  feet 
away,  which  is  close  to  a  magnetic  needle  C,  and  we  ap- 
proach a  magnet  D  to  the  first  coil  A,  then  the  needle 
is  momentarily  deflected.  The  needle  C  is  far  enough 
away  not  to  be  under  the  directing  influence  of  the  mag- 


69 

net  D.  What  takes  place  is  this:  The  sphere  surround- 
ing the  magnet  pole  in  its  approach  affects  the  coil  A,  and 
this  disturbance  in  space  is  the  cause  of  the  flow  of  an  elec- 
tric current  in  coil  A,  which,  passing  through  the  coil  B, 
disturbs  the  air  surrounding  it  and  changes  it  into  a  mag- 
net, which  in  turn  acts  on  the  compass  needle.  Here  we  have 
one  of  the  earliest  transmissions  of  power  to  a  distance. 

Returning  now  to  our  simple  magnet  (Fig.  39).  it  will  be 
clear  and  in  accordance  with  facts  that  if  a  loop  of  wire, 
placed  between  the  poles  of  a  horseshoe  magnet  and  con- 
nected to  a  delicate  instrument  for  measuring  electric  cur- 
rents, is  turned  between  the  poles  of  this  magnet,  such  turn- 


ing produces  a  temporary  current  which  affects  and  deflects 
the  needle  of  the  instrument.  An  electric  current  is  gen- 
erated which  flows  from  the  loop  to  the  instrument  and 
back  again,  with  the  effect  of  deflecting  the  needle  of  the 
instrument.  What  has  been  found  is  that  taking  a  magnet 
and  turning  a  coil  of  wire  in  its  sphere  of  activity,  or  (as 
it  is  called  technically)  in  its  magnetic  field,  an  electric  cur- 
rent is  created  or  generated  in  this  coil.  The  reader  will  now 
see  that  if  this  simple  magnet,  with  the  loop  or  a  coil  placed 
between  its  poles,  is  conveniently  arranged  on  a  shaft  so  as 
to  turn  it  continually  in  the  same  direction  (Fig.  40),  a  cur- 
rent will  be  produced  that  will  last  for  some  time  instead  of 
simply  an  impulse  of  current ;  this  constitutes  a  dynamo 


70 


in  its  simplest  form.  Of  course  such  an  arrangement  gives 
but  very  weak  currents  and  is  not  a  commercial  device,  ow- 
ing to  its  primitive  mechanical  arrangement,  and  also  owing 
to  the  weakness  of  the  permanent  magnet,  but  this  funda- 


mental idea  can  be  recognized  in  any  and  all  of  our  modern 
macihnes. 

Now  let  us  start  once  more  with  our  permanent  magnet 
and  go  through  the  evolution  until  we  reach  the  dynamo 
of  to-day.  Fig.  28  shows  the  permanent  horseshoe  mag- 
net with  its  keeper  in  place.  Fig.  41  shows  the  keeper  or 
armature,  as  we  will  call  it  hereafter,  some  distance  from 
the  poles,  with  the  field  of  activity  in  the  space  between  the 


FIG.  44. 


poles  and  the  armature.  The  armature,  under  the  influ- 
ence of  the  magnet,  becomes  also  a  magnet  and  must  ex- 
hibit poles,  which  are  indicated  by  the  letters  N  S,  N  S,  in 
such  a  way  that  a  south  pole  of  the  armature  will  stand 
before  a  north  pole  of  the  magnet.  Under  these  condi- 


71 

tions  the  force  exerted  causes  mutual  attraction  between  the 
magnet  and  its  armature,  resulting  in  a  motion  of  the  smaller 
piece,  which  moves  toward  the  magnet,  where  all  motion 
stops  when  it  rests  against  the  poles.  If  we  now  wind  a  coil 
around  the  armature,  we  would  obtain  a  temporary  current 
which  lasts  as  long  as  the  armature  is  approaching  the  poles 
(Fig.  42),  but  as  soon  as  the  armature  comes  to  rest  the 
current  ceases.  In  a  dynamo  it  is  desired  to  produce  cur- 
rents continually,  and  therefore  it  is  necessary  to  modify 
the  form  and  relationship  of  the  armature  to  the  magnet. 
This  is  shown  in  Fig.  43.  In  this  case  the  armature  is 


mounted  on  a  spindle,  a  cylindrical  piece  of  iron,  which, 
magnetically  considered,  is  a  bar  as  in  Fig.  41.  Fig.  44 
shows  a  magnet  like  Fig.  43,  with  the  wires  wound  around 
the  cylindrical  armature  core.  The  wires  and  the  shaft  are 
shown  in  section.  The  wire,  which  is  to  be  rotated  in  the 
space  of  magnetic  activity,  is  placed  as  near  the  poles  as  pos- 
sible, as  shown  in  section  in  Fig.  44.  This  figure  is  ob- 
tained by  placing  the  magnet  in  the  plane  of  the  leaf  or  book 
(Fig.  45).  The  armature  and  wires  lie  at  right  angles,  pen- 
etrating through  all  the  leaves.  If  the  armature  in  Fig.  45 
be  cut  off,  the  end  that  projects  on  top  is  shown  in  Fig.  44. 
To  collect  the  currents  generated  and  bring  them  to  devices, 
such  as  lamps  or  motors,  we  have  to  make  some  provision 


72 


for  collecting  the  electric  current  from  the  rotating  arma- 
ture to  stationary  points.  This  is  done  by  connecting  the 
ends  of  the  rotating  coils  to  metallic  contact  pieces  or  rings, 
which  will  be  explained  later. 

To  produce  strong  currents  strong  magnets  are  needed, 


FIG.  47. 

and  it  was  found  that  permanent  steel  magnets  were  weak- 
ened when  an  armature  with  winding  was  made  to  gen- 
erate heavy  electric  currents.  It  was  further  found  that 
soft  iron,  when  wound  with  coils  through  which  a  current 
was  sent,  became  a  far  more  powerful  magnet  than  could 
be  obtained  in  any  other  way.  Therefore  it  became  the  prac- 


73 


tice  to  use  wrought  iron,  cast  iron  or  soft  steel  magnets  for 
dynamos,  and  to  magnetize  them  by  a  winding  through  which 
an  electric  current  is  sent  as  long  as  the  machine  is  working. 
Fig.  46  shows  our  simple  magnet  provided  with  energizing 
coils,  which,  to  distinguish  them  from  the  windings  on  the 
armature,  are  called  the  field  magnet  windings,  or,  in  short, 
the  field  windings,  because  they  belong  to  that  magnet  which 
establishes  the  field  in  which  the  other  part  or  armature  ij> 


FIG.  48. 


to  rotate.     Between  the  magnet  poles  is  the  armature  with 
a  winding  and  contact  devices. 

"If  we  now  compare  the  complete  dynamo  with  the  orig- 
inal magnet,  we  find  that  the  only  difference  between  them 
is  that  the  dynamo  is  made  more  powerful  than  the  magnet 
by  the  application  of  the  coils,  and  the  differences  in  the 
armatures  are  that  the  motion  is  changed  from  a  lateral  to 
a  rotary  one ;  further,  that  the  armature  is  provided  with  a 
winding  and  a  device  for  conveniently  taking  off  the  cur- 
rent generated  by  the  rotating  of  the  armature  winding  in 
the  sphere  of  energy  of  the  magnet.  The  reader  will  now 
clearly  see  that  there  is  no  frictional  contact  required  be- 
tween the  armature  and  the  field  magnet,  an  erroneous  view 


74 


so  frequently  expressed  by  people  not  conversant  with  the 
subject. 

We  are  now  prepared  to  look  critically  at  any  kind  of  a 
dynamo,  from  the  simplest  and  weakest  to  the  largest  ma- 
chines built  to-day,  without  confusion  and  without  the  idea 
of  great  complication  as  regards  the  nature  of  its  operation, 
for  now  the  single  magnet  with  the  single  loop  between  the 
poles  will  be  ever  present  before  the  mental  eye. 


Let  us  examine  in  this  way  a  few  of  the  types  of  dynamos 
used  in  every-day  practice.  Fig.  47  shows  the  outline  of 
an  Edison  dynamo,  one  of  the  older  types,  still  in  use  in 
some  stations.  The  horseshoe  magnet  with  its  windings 
will  readily  be  recognized  in  this  machine.  It  is  built  with 
its  poles  downward  and  its  armature  between  the  poles, 
which  are  extended  so  as  to  surround  the  armature.  Fig. 
48  shows  a  front  and  side  view  of  the  armature,  the  iron 
core  being  completely  covered  by  the  wire.  On  the  right 
side  may  be  seen  the  contact  terminals,  called  the  commu- 
tator, which  is  marked  A.  In  Fig.  25  was  shown  a  large 


75 

railway  generator  capable  of  driving  a  great  many  cars.  Fig. 
49  is  a  skeleton  of  a  multipolar  field  magnet,  which  shows  a 
magnet  with  four  poles  and  consists  of  four  horseshoe  mag- 
nets, one  of  which  is  shown  shaded.  The  armature  is  shown 
located  between  the  poles. 

This  elementary  description,  explaining  the  nature  of  the 
generation  of  an  electric  current,  shows  clearly  how  simple 
is  the  principle  underlying  an  electric  machine.  It  is  a 
magnet  at  rest,  combined  with  a  rotating  piece  of  iron 
wrapped  with  wire,  that  constitutes  a  dynamo;  and  further- 
more, a  machine  that  is  used  as  a  dynamo  may  also  be  used 
as  a  motor.  The  name  dynamo  or  motor  changes  with  the 
service  to  be  rendered.  If  the  machine  sown  in  Fig.  47  be 
driven  by  a  steam  engine,  and  is  supplying  electric  current, 
it  is  a  dynamo;  if,  however,  an  electric  current  is  applied  to 
it,  and  it  does  mechanical  work,  it  is  a  motor.  These  dif- 
ferences should  be  clear  in  the  mind  of  the  reader.  If  there 
are  parts  he  does  not  understand  clearly,  he  should  discuss 
the  subject  with  such  persons  of  his  acquaintance  who  are 
competent  to  explain  the  matter  to  him. 


CHAPTER  II. 

THE  ELECTRIC  RAILWAY   MOTOR  AND  CAR  EQUIPMENT. 

We  are  now  ready  to  look  into  the  details  of  an  electric 
railway  motor.  In  Chapter  I  were  explained  the  principles 
on  which  all  dynamos  and  motors  are  built.  We  found  a 
motor  to  be  simply  a  magnet  in  which  the  magnetism  is 
produced  by  the  electric  current,  and  in  which  one  part, 
called  an  armature,  is  caused  to  revolve  by  magnetic  attrac- 
tion between  it  and  the  poles  of  other  parts,  called  the  field 
magnets.  We  have  also  learned  how  the  electric  current  is 
transmitted  through  wires,  and  what  precautions  are  neces- 
sary to  insulate  or  confine  it  to  the  proper  wires  or  con- 
ductors. 

Let  us  go  more  into  the  details  of  the  internal  working 
of  the  armature  of  the  dynamo  or  motor,  and  show  the  rea- 
son why  in  one  case  large  engines  are  used  to  produce  the 
electric  current,  and  while  at  other  times  the  armature  will 
turn  itself  and  give  out  energy.  In  Fig.  48  is  shown  an  ar- 
mature complete.  It  consists  of  a  shaft  on  which  is  mounted 
an  iron  core  closely  wrapped  with  wire,1  and  the  ends  of  the 
wire  coils  are  connected  to  the  contact  terminals,  called  the 
commutator,  on  which  the  brushes  rest  to  collect  the  current. 
An  armature  is  represented  in  diagram  in  Fig.  50.  The  iron 
armature  core  A  is  shown  in  form  of  a  ring.  The  winding 
B  is  uniformly  wrapped  around  the  core,  and  every  three 
turns  a  wire  is  led  to  the  commutator  C,  which  is  divided 
into  eight  parts  because  the  winding  shows  eight  coils.  The 
number  of  coils  varies  on  different  kinds  of  armatures. 


77 

The  commutator  consists  of  copper  bars  insulated  from 
one  another  by  mica.  These  bars  form  the  ends  of  the 
armature  coils.  They  are  made  heavier  than  the  wires  so 
as  to  last  a  long  time,  being  exposed  to  wear  by  rubbing 
contact,  and  to  be  detachable  when  worn  out.  On  the  com- 
mutator rest  the  brushes  D,  Di.  If  the  armature  is  tra- 
versed by  a  current  entering  at  brush  D,  as  for  instance  when 
it  is  used  as  a  motor,  the  current  passes  to  segment  I,  and 
from  there  through  connecting  wire  a  to  the  armature  wire 
proper.  Here  it  has  a  double  pass,  as  shown  by  the  arrows. 


Half  the  current  will  follow  the  direction  indicated  by  the 
arrows  on  the  upper  half  of  the  ring,  and  the  other  part  of 
the  current  will  follow  ihe  wires  wound  on  the  lower  half  of 
the  armature  core.  The  two  currents  unite  again  wire  e, 
enter  segment  5  brush  Di,  and  leave  the  armature.  This 
flow  takes  place  in  whatever  position  the  armature  may  be. 
For  instance,  assuming  the  brushes  D,  Di  stationary  and  the 
armature  turning ;  if  the  armature  has  turned  so  far  around 
that  segment  2  would  be  under  the  brush  D,  then  segment 
6  would  be  under  brush  Di.  The  current  would  go  to  the 
armature  winding  through  b  and  leave  it  by  way  of  f.  In 


78 

this  way  each  one  of  the  segments  and  connecting  wires  has 
to  perform  in  succession  its  work.  The  current  in  going 
around  the  core  makes  a  magnet  out  of  the  iron,  as  indicated 
by  the  letters  N,  S. 

For  the  sake  of  convenience  in  understanding,  the  arma- 
ture core  may  be  also  considered  divided  into  two  half  rings, 
as  in  Fig.  51,  the  upper  and  lower;  then  the  current  flowing 
around  the  upper  half  makes  it  a  magnet,  and  similarly  the 


FIG.  51. 


current  in  the  lower  half  will  make  that  half  become  a  mag- 
net. The  poles  are  marked  N  and  S.  The  poles  caused  by 
each  half  of  the  current  are  indicated  on  the  ring.  An  N 
pole  on  one  side  and  an  S  pole  on  the  opposite  side  in  each 
half  is  produced,  and  both  together  make  again  one  N  pole 
and  one  S  pole,  but  of  double  the  strength.  As  long  as  the 
brushes  stand  in  this  position  the  magnetic  poles  will  stay 
in  space  in  the  same  position,  however  much  the  armature 
may  rotate,  because  just  as  many  turns  are  leaving  the  brush 
on  one  side  as  are  brought  under  it  from  the  opposite  side. 


79 

The  iron  ring  wrapped  with  the  armature  wire  repre- 
sents in  reality  two  half  circular  magnets 'butting  together 
with  similar  poles.  Whether  these  are  curved  as  is  Fig.  51, 
or  have  another  form,  for  instance,  being  straight  bar  mag- 
nets, does  not  alter  anything  in  the  nature  of  the  armature. 
Nor  is  there,  as  far  as  principle  is  concerned,  any  difference 
between  a  ring  armature,  shown  in  Fig.  50,  and  a  drum  ar- 
mature. An  armature  made  for  a  street  railway  motor  is 
generally  made  of  thin  discs  mounted  in  a  compact  way  on 
a  shaft  (Fig.  52).  The  wire  in  this  case  has  to  be  all  ap- 
plied externally.  It  cannot  be  threaded  through  the  center 


as  in  Fig.  50,  but  the  results  is  the  same.  Fig.  53  is  a  dia- 
gram indicating  a  railway  motor  with  an  iron  core  made  of 
discs  and  the  magnetizing  copper  wire  wound  all  around  the 
surface. 

The  diagram  represents  the  armature  in  section.  Now 
suppose  the  brushes  to  be  set  as  they  are  in  Fig.  50,  then 
the  current  flowing  in  the  coils  with  which  the  armature  core 
is  wound  will  cause  N  and  S  poles  in  the  armature  as  in- 
dicated. Current  is  also  sent  through  the  coils  on  the  field 
magnets,  causing  N  and  S  poles  in  the  magnet  as  indicated. 
It  will  be  evident  that  the  S  pole  of  the  armature  will  en- 
deavor to  place  itself  in  front  of  the  N  pole  of  the  field  mag- 
net, being  attracted  by  it  and  at  the  same  time  repelled  by 


80 

the  S  pole  near  it.  Similarly  the  N  pole  of  the  armature  will 
try  to  get  in  front  of  the  S  field  pole,  being  attracted  by  this 
pole  and  repelled  by  the  N  pole;  but  as  the  brushes  are  sta- 
tionary, the  magnetic  poles  S,  N  of  the  armature  remain 
fixed  in  space  between  the  poles,  while  the  conductors  car- 
rying the  current  and  the  core  on  which  they  are  wound  are 
turning  in  the  direction  of  the  arrow  as  long  as  a  current  is 
conducted  into  the  armature. 

In  a  motor,  therefore,  the  electrical  energy  furnished  by 
some  outside  source  causes  rotation  capable  of  developing 
mechanical  energy.  In  a  dynamo  it  is  just  the  opposite. 
There  is  no  electrical  energy  given ;  it  has  to  be  produced. 


The  wire  coils  passing  in  front  of  the  magnet  poles  gen- 
erate current. 

Fig.  54  illustrates  this  action.  The  field  magnet  N  S 
changes  the  armature  into  a  magnet  with  the  poles  as  indi- 
cated, the  S  pole  of  the  armature  approximately  facing  the 
N  pole  of  the  field  and  the  N  pole  of  the  armature  nearly 
facing  the  S  pole  of  the  field  magnet.  There  exists  mutual 
attraction  between  the  armature  and  the  field  magnet.  To 
generate  a  current,  the  armature  must  be  turned  between 
the  energized  field  magnet  poles,  which  is  equivalent  to  at- 
tempting the  pulling  away  the  armature  poles  from  under 
the  field  'poles.  This  we  know  from  the  first  experimnent 
mentioned  in  the  book  means  the  expenditure  of  energy. 

We  can  now  look  more  intelligently  at  the  parts  of  a 


81 


modern  electric  railway  motor  than  we  could  when  we  first 
went  through  the  shops.  We  have  already  seen  the  external 
parts  of  a  motor  in  Chapter  i,  Part  i,  Figs.  7  tq  16.  From 
the  foregoing  explanations  we  are  now  in  a  position  to  ex- 
amine the  various  internal  parts  of  an  electric  motor.  Fig. 


FIG.  55. 


55  shows  a  railway  motor  with  its  frame  opened,  giving  a 
view  of  its  interior  parts.  The  armature,  A,  is  mounted 
upon  a  shaft  and  at  one  end  of  the  armature  is  the  com- 
mutator C,  consisting  of  a  cylinder  of  insulated  copper  bars, 
to  which  the  ends  of  the  armature  coils  are  connected.  Sur- 
rounding the  armature  are  four  field  magnets,  or  poles,  P, 
around  which  are  wound  coil  of  wire  to  magnetize  them  for 


82 

the  purpose  previously  explained.  The  brushes,  B,  conduct 
the  current  to  and  from  the  armature  through  their  contact 
with  the  commutator.  These  brushes  consist  of  carbon 
blocks  which  are  held  in  brush  holders  and  which  are  pressed 
against  the  commutator  by  springs.  The  path  of  the  current 
through  the  motor  is  as  follows :  Starting  at  one  of  the 
brushes  the  current  passes  through  all  the  coils  of  wire  upon 
the  armature,  beginning  at  whatever  commutator  bar  the 
brush  happens  to  rest  upon,  and  comes  out  upon  another 
commutator  bar  under  the  second  brush.  From  this  brush 
the  current  is  led  through  all  the  field  coils  wound  around 
the  poles  surrounding  the  armature,  and  this  completes  the 
circuit  through  the  motor.  With  the  current  flowing 
through  both  the  armature  and  the  field  coils,  both  the  ar- 
mature and  the  field  become  magnets,  and  each  attracts  the 
other  in  such  a  way  as  to  cause  the  armature  to  turn  as  pre- 
viously explained.  To  reverse  the  direction  in  which  the 
armature  revolves,  which  reverses  the  direction  of  the  car, 
it  is  only  necessary  to  change  the  direction  in  which  the  cur- 
rent flows  through  the  armature,  allowing  the  current  to 
flow  through  the  fields  in  the  same  direction  as  before,  or  we 
can  also  reverse  the  direction  of  revolution  by  permitting  the 
current  to  flow  in  the  same  direction  through  the  armature 
and  reversing  its  direction  through  the  field  coils.  If  the 
armature  current  is  reversed  the  magnetism  in  the  armature 
is  reversed,  the  north  pole  becoming  a  south  pole  and  the 
south  pole  a  north  pole.  In  order  to  reverse  the  current  in 
the  armature  the  wires  from  the  armature  brushes  are  led 
to  the  controller  independently  from  the  terminals  of  the  field 
coils,  so  that  the  connections  of  the  armature  terminals  can 
be  reversed  at  the  controller  when  it  is  desired  to  reverse 
the  direction  of  rotation  of  the  motor.  For  this  reason 
there  will  always  be  at  least  four  wires  leading  out  from  the 
motor. 


83 

We  will  now  trace  the  electrical  circuit  through  the  car. 
The  current,  as  we  know,  comes  from  the  power  house 
through  the  feed  wires  and  trolley  wire,  and  flows  through 
the  trolley  wheel  down  the  trolley  pole  to  the  trolley  base. 
This  base  is  insulated  from  the  ground  by  the  wood  which 
forms  the  car  body.  From  the  trolley  base  a  wire  conducts 
the  current  to  the  canopy  switch  over  one  platform,  and 
passing  through  this  switch  it  flows  through  another  wire  to 
the  canopy  switch  over  the  other  platform  and  from  there  a 


FIG.  56. 

wire  generally  concealed  in  a  corner  post  of  the  car  carries 
the  current  to  the  car  fuse  box,  mentioned  in  Chapter  I,  Part 
i.  The  canopy  switch,  Fig.  56,  is  also  sometimes  called  the 
main  motor  switch,  the  overhead  switch  or  the  auxiliary 
switch.  These  switches  are  generally  provided  with  what 
is  known  as  a  blow-out  magnet  coil,  for  the  purpose  of  blow- 
ing out  the  arc  when  the  switch  is  opened.  The  next  piece 
of  apparatus  in  the  circuit  is  the  fuse  box,  which  is  a  device 
for  protecting  the  motors  from  an  excessive  flow  of  current. 


84 


All  the  current  flowing  through  the  car  motors  passes 
through  this  fuse  box,  of  which  there  are  several  styles  on 
the  market.  The  simplest  fuse  consists  merely  of  a  piece 


FIG.  57. 

of  soft  wire  generally  made  of  some  aHoy  of  lead  having  a 
low  current  carrying  capacity.  This  piece  of  fuse  wire  will 
melt  and  open  the  electric  circuit  whenever  the  current 
flows  through  the  motors  of  such  an  amount  as  might  burn 
the  cotton  insulation  on  the  coils  of  the  armature  or  the  field 


magnet.  When  too  much  current  is  permitted  to  flow 
through  any  wire  it  becomes  heated  and  the  greater  the 
amount  of  current  the  hotter  the  wire  becomes.  If.  there- 


85 

fore,  something  should  happen  on  the  car  to  allow  too  much 
current  to  flow  through  the  motors,  the  wire  upon  their  ar- 
matures and  fields  would  become  heated  so  as  to  burn  the 
insulation  upon  them,  and  would  eventually  be  melted  if  the 
circuit  were  not  protected  with  a  fuse  which  would  melt 
when  the  current  exceeded  a  certain  predetermined  amount. 
The  fuse  is  frequently  a  short  length  of  metal  connected  be- 
tween two  binding  posts,  and  of  a  material  that  will  melt  at 
a  very  low  temperature,  although  sometimes  a  small  copper 
wire  is  used.  When  copper  is  used  it  must  be  of  a  size  much 


smaller  than  any  of  the  other  wires  on  the  car,  so  that  it  will 
melt  before  any  other  of  the  wires  in  the  circuit  can  get 
dangerously  hot. 

The  Westinghouse  Company  employs  a  fuse  which  has 
to  be  taken  out  of  the  box  with  its  supporting  blocks  before 
it  can  be  renewed  (Fig.  58),  but  with  this  exception  the 
usual  fuse  box  consists  simply  of  two  terminals  fixed  inside 
the  fuse  box  between  which  the  fuse  is  clamped,  as  in  the 
General  Electric  fuse  box  (Fig.  57). 

In  addition  to  the  bare  wire  fuses  described  above,  there 
are  various  covered  fuses  such  as  the  D.  E.  W.  fuse,  Fig.  59, 
and  the  Noark  fuse,  Fig.  60.  The  latter  has  a  fusible  con- 


86 

ductor  which  is  enclosed  in  a  tube  and  around  the  con- 
ductor is  a  special  filling  which  prevents  any  arc  or  flash 
under  short  circuits.  A  fuse  of  this  kind  is  a  great  im- 
provement over  the  old-fashioned  bare  wire  fuses,  as  they 
do  not  blow  with  the  loud  report  and  heavy  flash  which  ac- 
company the  blowing  of  a  bare  fuse.  They  are  also  of  ad- 
vantage in  not  blistering  the  varnish  and  paint  of  the  car, 
which  frequently  happens  with  the  uncovered  fuse.  An- 


other advantage  of  these  fuses  is  that  they  are  inserted  in 
the  fuse  box  by  simply  pushing  the  tube  into  its  seat  be- 
tween clamping  springs,  and  there  are  no  thumb  screws  to 
be  manipulated,  which  is  a  difficult  matter  in  severe  weather. 
Automatic  circuit  breakers  have  recently  been  used  to  a 
large  extent  to  take  the  place  of  the  fuse,  and  they  are  prefer- 
able to  fuses  for  a  number  of  reasons,  the  chief  of  which 
are  that  they  may  be  arranged  to  break  the  circuit  when  the 
current  exceeds  any  predetermined  amount  with  much  more 
accuracy  than  a  wire  fuse,  and  they  are  thrown  into  circuit 


87 


again  simply  by  the  movement  of  a  handle  without  the  neces- 
sity of  replacing  any  of  the  parts,  as  with  the  fuse.  There  are 
a  number  of  circuit  breakers  on  the  market,  one  of  which, 
called  the  I.  T.  E.  circuit  breaker,  is  shown  in  Fig.  61,  but 
they  are  all  designed  practically  upon  the  same  principle. 
The  principal  parts  of  the  automatic  circuit  breaker  are  a 
switch  which  closes  against  a  spring,  and  which  is  held  in 
its  closed  position  by  means  of  a  trip.  In  the  circuit  of  the 
machine  is  placed  a  magnetic  coil,  the  function  of  which  is 


FIG.  61. 


to  attract  an  armature  whose  movement  releases  the  trip, 
permitting  the  spring  to  throw  the  contact  surfaces  apart 
and  break  the  circuit.  The  cause  of  the  armature  being  at- 
tracted and  the  trip  released  is  that  the  magnet  coil  is  wound 
so  that  with  a  normal  amount  of  current  the  magnet  is  not 
strong  enough  to  attract  the  armature,  but  the  moment  an 
excessive  amount  of  current  is  used  the  strength  of  the  mag- 
net is  correspondingly  increased,  so  that  the  armature  is  at- 
tracted and  the  trip  released,  which  opens  the  circuit. 

The  next  device  on  the  car  to  which  the  current  is  led  is 
the  lightning  arrester.    This  is  a  device  to  deflect  lightning 


or  atmospheric  discharges  from  the  circuit  to  the  ground 
before  they  have  an  opportunity  to  reach  the  motors  or  other 
electrical  apparatus  on  the  car.  There  is  a  strong  tendency 
for  a  lightning  discharge  to  take  the  shortest  and  most  direct 
path  to  the  ground,  and  it  will  readily  arch  over  a  small  gap 
or  air  space  or  will  pierce  through  insulating  materials  to 
the  ground.  If  it  were  not  for  the  lightning  arrester,  the 


True  A  and  Grouncf 


FIG.  62.  FIG.  63. 

lightning  would  frequently  jump  through  the  insulation 
of  the  armatures  or  field  magnets  of  the  car  motor,  and  while 
the  very  small  current  of  the  lightning  discharge  would  do 
no  harm  of  itself,  the  arc  which  it  would  establish  in  jump- 
ing to  the  ground  would  be  followed  up  by  the  line  current 
from  the  station,  which  would  burn  ont  the  windings  im- 
mediately. The  tendency  of  lightning  to  jump  to  the  ground 
by  the  shortest  path  is  the  principle  upon  which-  most  all 
lightning  arresters  are  designed.  These  devices  usually  con- 


89 

sist  of  some  arrangement  whereby  the  lightning  can  easily 
pass  down  the  wire  across  to  the  ground  by  jumping  be- 
tween points  set  a  small  fraction  of  an  inch  apart.  Various 
provisions  are  made  by  different  manufacturers  to  prevent 
the  current  from  the  power  house  from  following  the  light- 
ning when  it  is  deflected  to  earth.  Fig.  62  shows  a  diagram 
of  the  connections  of  the  lightning  arrester.  One  terminal 
is  connected  to  the  wire  from  the  trolley  and  the  other  to 
the  motor  truck  and  therefore  to  the  ground.  The  lightning 
jumps  across  between  the  points  and  is  thus  led  to  the  earth. 
Fig.  63  shows  a  Carton  arrester.  In  it  may  be  seen  the  two 
carbon  points  indicated  by  an  arrow  between  which  the 


lightning  jumps  on  its  way  to  earth.  In  order  to  break  this 
special  circuit  after  the  lightning  has  passed  so  that  the  cur- 
rent from  the  dynamo  cannot  follow  by  the  same  path  that 
is  taken  by  the  lightning  to  earth,  the  circuit  to  the  lightning 
arrester  is  automatically  broken  by  an  electro  magnet  which 
pulls  the  two  carbons  apart  as  soon  as  current  flows  through 
the  coil  C.  It  will  be  seen  that  the  circuit  of  the  lightning 
arrester  or  by-pass  is  constantly  open  except  when  tempo- 
rarily closed,  as  the  lightning  flash  crosses  it,  and  even  then 
it  is  a  circuit  of  very  high  resistance.  It  is  therefore  clear 
that  while  the  lightning,  arrester  is  connected  to  the  trolley 
wire,  yet  no  current  from  the  trolley  line  goes  through  it.  A 
kicking  coil,  Fig.  64,  is  used  in  connection  with  the  lightning 


90 

arrested,  and  an  inductive  resistance  such  as  this  coil  is  the 
only  resistance  that  offers  hindrance  to  the  passage  of  static 
electricity-  or  lightning.  The  kicking  coil  is  put  in  the  cir- 
cuit immediately  after  the  lightning  arrester  and  its  induc- 
tive resistance  tends  to  drive  the  discharge  through  the  ar- 
rester before  it  reaches  the  motors  or  other  apparatus.  Fig. 
65  shows  the  Wurtz  non-arcing  lightning  arrester  with  the 
outside  cover  removed.  The  principle  upon  which  this  ar- 
rester is  based  is  that  a  discharge  will  pass  over  a  non-con- 


FIG.  65. 


ducting  surface,  such  as  wood,  more  readily  than  through  an 
equal  air  gap,  and  the  discharge  will  take  place  still  more 
readily  if  a  pencil  or  carbon  mark  be  drawn  over  the  non- 
conducting surface.  In  order  to  maintain  a  dynamo  arc, 
fumes  or  vapors  of  the  electrodes  must  be  present.  The  in- 
strument is  constructed  with  two  metal  electrodes  mounted 
upon  a  block  of  hard  wood  with  charred  or  carbonized 
grooves  upon  it  to  provide  a  path  for  the  discharge.  An- 
other block  of  wood  is  fastened  closely  upon  the  first  block, 
entirely  covering  the  grooves  and  electrodes.  The  discharge 
takes  place  over  the  charred  grooves  which  provide  an  easy 


91 

path  for  it,  and  as  there  is  no  room  for  vapor  between  the 
tightly  fitting  blocks  no  arc  can  be  formed.  Fig.  66  shows 
the  General  Electric  type  of  lightning  arrester  for  trolley 
cars. 

After  the  line  current  has  passed  the  point  where  the  light- 
ning arrester  is  connected,  it  flows  through  what  is  called  the 
kicking  coil  previously  mentioned.  The  object  of  this  is  to 
aid  in  making  it  difficult  for  the  lightning  to  flow  toward  the 
motors,  owing  to  an  inductive  kick  in  the  spiral  winding, 
and  to  increase  the  liability  of  its  going  to  ground  through 
the  lightning  arrester. 

After  leaving  the  choke  coil  the  current  enters  one  of  the 
many  wires  conveniently  held  by  a  hose.  This  wire  is  con-' 
nected  to  both  car  controllers.  A  number  of  other  wires 
lead  from  each  controller  to  motors  and  regulating  resist- 
ance. After  leaving  the  motors  the  current  flows  to  a  wire 
which  is  securely  fastened  to  the  iron  or  frame  of  the  motor, 
from  which  the  circuit,  continues  through  the  various  motor 
supports  to  the  car  truck  and  car  axle,  then  to  the  wheel 
rims  through  the  rails  back  to  the  generator.  Next  in  im- 
portance to  the  motors  are  the  car  controllers.  As  the  mo- 
torman  has  chiefly  to  do  with  the  controllers  they  will  be 
treated  in  a  subsequent  chapter, 


CHAPTER  III. 

CONTROLLERS. 

For  controlling  the  speed  of  electric  cars  three  general 
methods  have  been  employed,  two  of  which,  however,  are 
practically  obsolete  to-day.  One  method  is  by  means  of  a 
rheostat,  which  was  the  system  adopted  by  the  Thomson- 
Houston  Co.  In  the  Thomson-Houston  method  of  con- 
trol the  motors  are  connected  permanently  in  paral- 
lel, and  the  rheostat  is  inserted  in  series  with  the 
two  motors,  and  contains  sufficient  resistance  to  re- 
duce the  starting  pressure  to  less  than  half  of  the  total  volt- 
age. This  resistance  is  gradually  cut  out  until  the  full  volt- 
age of  the  circuit  passes  through  the  motors  when  the  car 
reaches  its  maximum  speed.  There  are  two  types  of  rheo- 
stats made  by  the  Thomson-Houston  Co.  known  as  type 
D~5i  and  D-8i.  The  former  is  semi-circular  in  shape,  and 
the  latter  is  round.  Another  method  of  motor  control  for 
street  cars  is  that  of  the  Sprague  system  in  which  the  field 
coils  are  divided  into  several  sections,  the  sections  be- 
ing connected  in  series  and  also  in  series  with  the 
armature  in  starting  the  car,  and  changing  by  suc- 
cessive steps  of  the  controller  until  they  are  all  in 
parallel,  and  in  parallel  with  the  armature,  when  the 
car  attains  its  maximum  speed.  A  starting  rheostat  is  also 
used  with  this  method  of  control,  but  is  in  series  only  on  the 
first  notch  of  the  controller  when  the  car  is  starting  from 
rest.  Both  of  these  systems  are.  now  practically  out  of  use, 


93 

and  can  only  be  found  on  cars  equipped  many  years  ago,  but 
as  they  are  liable  to  be  met  with  on  some  of  the  older  roads, 
a  short  reference  and  description  of  them  has  been  included. 
Of  these  two  systems  the  Sprague  system  is  the  most  eco- 
nomical in  the  use  of  current,  but  owing  to  the  complication 
of  the  windings,  is  more  liable  to  derangements  and  burn 
outs.  With  the  straight  rheostatic  method  there  is  .  no 
change  whatever  in  the  connections  of  the  motor  fields,  and 
while  this  method  is  less  efficient  than  the  other,  its  freedom 
from  accidents  and  burn  outs  is  a  distinct  advantage. 

The  series  parallel  method  of  control  which  is  now  uni- 
versally used,  and  which  has  supplanted  all  other  methods, 
consists  in  grouping  the  motors  on  the  car,  together  with  the 
starting  rheostat,  in  series  and  gradually,  through  the  suc- 
cessive steps  of  the  controller,  changing  them  to  parallel  con- 
nection when  the  car  attains  its  greatest  speed.  A  large  num- 
ber of  controllers  of  both  the  General  Electric,  Westinghouse 
and  other  makes,  are  described  in  the  following  pages.  It 
may  be  stated,  however,  that  the  type  K  General  Electric 
controllers,  are  the  ones  most  commonly  used. 

The  car  controller  is  a  combination  of  switches  adapted 
to  control  the  speed  of  the  motors  by  admitting  more  or  less 
electrical  energy  to  the  motors  as  the  case  may  require. 
These  changes  of  connections  may  be  made  by  a  number  of 
independent  and  separate  switches,  but  if  this  were  done 
many  switches  would  be  required,  and  they  would  be  slow 
and  awkward  to  operate  and  would  occupy  too  much  room. 
Experience  has  shown  that  a  circular  contact  drum  is  the 
quickest  acting  and  most  suitable  device  on  which  a  great 
many  changes  of  connections  can  be  made  simply  and  easily. 
The  purpose  of  the  controller  is  threefold : 

1.  To  connect  the  motors  into  the  circuit  so  that  current 
can  flow  through  them. 

2.  To  regulate  the  amount  of  current  flowing  to  the  mo- 


94 

tors  so  as  to  make  a  gradual  start  and  control  the  speed  of 
the  car. 

3.    To  govern  the  direction  of  travel  of  the  car. 

The  electrical  pressure  on  the  trolley  line  (technically 
called  voltage)  is  kept  practically  constant  at  the  power 
house.  Therefore,  if  the  current  at  full  pressure  were  ad- 
mitted suddenly  to  the  motors,  and  no  means  provided  to 
.allow  it  to  rise  gradually,  we  would  have  to  expect  a  similar 
abrupt  and  sudden  start  by  the  motors  from  a  state  of  rest. 
Admitting  the  full  current  would  be  a  strain  on  the  elec- 
trical parts,  and  similarly  the  sudden  start  from  rest  to 
high  speed  would  tax  the  bearings  and  other  mechanical 
supports  and  gears,  to  say  nothing  of  the  discomfort  which 
the  passengers  would  experience  by  the  jerk  with  which  the 
motors  would  start  the  car. 

To  control  the  amount  of  current  flowing  to  the  motor 
it  is  necessary  to  consume  a  portion  of  the  pressure  under 
which  the  current  flows  by  interposing  some  material  which 
offers  a  resistance  to  the  flow  of  the  current  until  the  motor 
has  been  gradually  increased  to  its  normal  speed.  All  the 
switches  or  contacts  for  such  grading  or  varying  of  resist- 
ance are  mounted  on  the  drum  of  the  controller,  while  the 
resistance  itself  is  generally  fixed  at  a  convenient  place  be- 
low the  car  body.  Substances  that  offer  resistance  to  the 
flow  of  current  are  iron  wire,  iron  strips  or  plates,  german 
silver,  etc.  For  street  railway  purposes  iron  plates  or  bands 
are  generally  used,  which  are  supported  in  an  iron  frame,  the 
turns  or  convolutions  being  insulated  from  each  other  and 
the  fire  proof  frame  by  mica.  The  complete  device  is  termed 
a  resistance,  though  some  call  it  rheostat  or  diverter.  Let  us 
assume,  for  the  sake  of  illustration,  that  the  total  length  of 
the  iron  resistance  band  is  40  ft.  in  divisions  of  10  ft.  each, 
these  divisions  being  connected  to  the  controller  terminals 
by  means  of  wires  mentioned  in  the  previous  chapter.  If 


95 

now  this  controller  were  placed  on  the  first  notch,  the  whole 
40  ft.  of  iron  band  would  be  in  circuit  with  the  motor,  and 
the  pressure  that  could  reach  the  motor  reduced  just  the 
amount  that  would  be  lost  in  the  40  ft.  of  iron  band.  Turn- 
ing the  controller  to  the  second  notch,  10  ft.  of  this  iron 
band  would  be  cut  out  so  that  but  30  ft.  would  be  in  cir- 
cuit. The  pressure  that  could  reach  the  motor  in  this  case 
would,  of  course,  be  greater  and  its  speed  would  increase. 
Turning  the  controller  to  the  third  notch,  but  20  ft.;  to  the 
fourth  notch,  but  10  ft.  of  the  resistance  would  be  left  in  the 


circuit,  and  at  the  fifth  position  the  resistance  would  be  out 
entirely,  causing  an  increase  of  speed  with  every  reduction 
in  resistance  and  a  maximum  speed  when  all  resistance  was 
cut  out. 

A  Westinghouse  resistance  or  diverter  is  shown  in  Fig. 
67.  Its  terminals  (by  which  as  just  explained  the  resist- 
ance is  subdivided)  are  led  to  the  controller.  In  order  to  clear- 
ly understand  all  the  different  changes  and  conditions  that 
take  place  by  means  of  the  controllers,  it  is  desirable  to  make 
the  reader  acquainted  first  with  the  different  modes  of  circuit 
connection  and  their  names,  and  then  immediately  apply  them 
to  standard  types  of  controllers.  After  the  preliminary  ex- 


96 


planation  one  type  of  each  make  in  general  use  will  be  de- 
scribed in  detail,  and  the  rest  will  be  understood  after  a 
simple  statement  of  the  successive  steps  and  changes  as  they 
take  place. 

If  several  parts  or  conductors  are  grouped  so  that  the 
total  current  flows  in  succession  through  all  parts,  they  are 
said  to  be  grouped  in  "series,"  as  for  instance  in  Fig.  68. 


Main  fuse  Resistance 


hVWVWH 


The  trolley,  the  main  fuse  and  the  resistance  carry  the  total 
current  that  goes  to  the  motors,  and  they  are  said,  or  each 
one  of  them  is  said,  to  be  in  series  with  the  motors.  The 
motors  are  also  in  series  with  each  other,  as  the  current  flows 
first  through  one,  then  through  the  other.  It  will  be  clear 
that  if  for  any  cause  the  main  fuse  would  melt,  there  would 
be  a  separation  between  the  trolley  pole  and  the  resistance 
and  the  current  could  not  flow. 

Another  mode  of  connection  is  called  "parallel"  or  "mul- 


97 


tiple"  connection.  This  is  shown  in  Fig.  69.  The  full  cur- 
rent supplied  to  a  car  goes  down  the  trolley  pole,  and  if  the 
motors  are  grouped,  as  shown  in  this  figure,  the  current 
will  divide  and  half  of  it  will  go  to  one  motor  and  the  other 
half  to  the  other  motor.  Where  the  circuits  of  the  motors 
are  connected  again  the  two  currents  join  and  flow  on  as 


one  through  the  car  wheel  and  rail.  The  two  motors  are 
connected  in  parallel  or  multiple  with  one  another.  How- 
ever, this  connection  is  not  restricted  to  motors  only.  Any 
two  or  more  conductors  placed  in  such  a  relation  that  the 
original  current  will  split  up  into  several  paths  and  join  at 
a  place  further  on,  are  called  connected  in  parallel,  or  shunt, 
or  in  multiple.  For  instance,  resistance  may  be  in  parallel 
with  or  in  shunt  circuit  to  the  field  coils  of  a  motor  (Fig. 
70) ,  a  connection  which  is  made  in  some  modern  controllers. 


A  third  way  of  connecting  parts  is  made  by  a  combina- 
tion of  the  two  above  ways.  Some  of  the  devices  with  re- 
lation to  others  are  in  series  with  one  another  and  in  par- 
allel with  others,  and  such  grouping  is  called  series-parallel 
or  parallel-series  connection,  Fig.  71  explaining  this  clearly. 
It  represents  a  condition  of  grouping  of  motors  on  large 
electric  locomotives.  There  are  shown  four  motors,  I,  2,  3 
and  4. 

Evidently  the  current  splits  at  A,  divides  into  two  cur- 
rents, one  of  which  flows  through  motors  i  and  2,  the  other 
through  motors  3  and  4.  The  volume  of  current  that  goes 


ft  e si*  tone  e 


through  motor  2  must  therefore  be  the  same  as  that  going 
through  motor  i,  and  the  relation  is  similar  between  mo- 
tors 3  and  4.  At  point  B  the  currents  join  and  the  total  cur- 
rent flows  to  the  car  axle  and  car  wheel  C.  In  this  combina- 
tion motors  i  and  2  are  in  series,  and  so  are  motors  3  and  4, 
but  the  i  and  2  combined  are  in  parallel  connection  to  3  and 
4  combined,  and  the  whole  combination  is  called  series-par- 
allel. 

Returning  now  to  the  controllers  themselves,  the  old  style 
(some  being  still  in  use)  installed  up  to  1893  consisted  of 
a  drum  with  contacts  mounted  thereon  wyhich  were  the  ter- 
minals for  trolley,  motor  armature,  motor  field,  resistance 
and  ground.  The  handle  or  lever  when  turned  to  the  left 


99 


caused  the  car  to  go  ahead,  when  turned  to  the  right  caused 
it  to  go  backward.  The  handle  was  in  the  "off"  position 
(meaning  that  circuit  was  open  and  the  current  turned  off 
from  the  motors)  when  it  stood  centrally  on  the  controller 
and  nearest  to  the  motorman  or  operator.  This  condition 
existed  in  the  controllers  of  the  Sprague,  Edison,  Westing- 
house,  Wightman  and  Steel  Motor  companies. 

The  old  Thomson-Houston  motor  has  no  such  cylinder 

_* from  Station      _. 


controller,  but  instead  two  brass  handles  which  turn  rods 
extending  below  the  car,  where  one  moves  an  arm  over  a 
sheet  iron  resistance  (see  Fig.  72)  for  gradually  cutting 
out  more  and  more  of  the  resistance,  and  the  other  handle 
operated  a  reversing  switch  which  caused  the  current  to 
flow  through  the  motor  so  as  to  reverse  the  direction  of 
rotation  of  the  armatures.  This  latter  handle,  placed  in 
the  forward  position,  causes  the  car  to  go  forward,  and 
when  pulled  as  far  back  as  possible  the  car  moves  back.  The 
upper  handle  or  controller  handle  is  moved  always  in  the 


100 

same  direction.  The  reversing  handle  should  never  be 
moved  unless  the  other  handle  is  in  the  "off"  position.  The 
connections  made  by  this  controller  or  rheostat  are  indicated 
by  the  diagram,  Fig.  73.  Let  A  represent  the  trolley  wire, 
B  the  trolley  pole,  C  a  contact  arm,  R  the  rheostat  or  resist- 
ance of  sheet  iron  in  zig-zag  shape,  the  circles  M,  M  indicat- 
ing the  motors  and  G  the  wheel  on  the  rail  H.  On  the  "off" 
piston  the  contact  C  is  not  in  touch  with  resistance  R,  there- 


fore no  current  will  leave  the  trolley  wire.  The  lever  C 
makes  contact  with  resistance  R,  and  cuts  it  out  gradually 
until  lever  C  is  brought  around  to  the  "on"  position,  when 
no  current  flows  through  the  resistance,  but  passes  directly 
from  the  end  of  the  contact  arm  to  the  motors,  where  it  di- 
vides, half  going  to  one  motor  and  half  to  the  other. 

In  car  equipments  installed  in  early  days,  the  connections 
between  controllers  and  motors  were  such  that  the  motors 
were  permanently  grouped  in  parallel  with  one  another.  The 
controllers  operating  these  equipments  are  known  as  paral- 


101 


lei  controllers.  One  sometimes  met  with  on  older  roads  is 
the  Westinghouse  parallel  controller  known  as  type  D.  Pro- 
jecting through  the  cover  plate  of  this  controller  is  the 
spindle  on  which  the  operating  handle  is  placed.  This  spindle 
carries  the  centrally  located  cylinder  with  its  ten  contact  cyl- 
inder bands.  Above  this  cylinder  or  drum  is  located  a  ratchet 
wheel  having  large  teeth,  and  as  many  notches  as  there  are 


positions  for  the  handle  or  changes  of  electrical  connections 
and  speeds.  In  this  ratchet  wheel  fits  a  small  roller  held  in 
an  arm  and  receiving  tension  by  a  spring.  By  means  of  this 
contrivance  it  is  possible  to  bring  the  controller  always  into 
the  same  position  for  each  point,  and  without  having  to  look 
at  the  handle  to  be  sure  that  it  is  exactly  on  a  notch. 

On  the  sides  of  the  drum  are  contact  fingers,  and  below 
the  drum  are  a  number  of  contact  blocks  provided  with 
screws  into  which  the  trolley  wire,  ground  wire  and  others 
are  attached  which  connect  to  the  resistance  or  diverter  and 


102 

motors.  The  circular  contacts  on  the  drum  are  not  of  the 
same  length ;  the  largest  ones  are  the  four  on  the  upper  end 
of  the  drum  and  the  lowest  one.  These  are  of  equal  length 
and  on  turning  the  drum  in  one  direction  or  the  other,  these 
five  connections  are  established  at  the  same  time.  In  this 
first  position,  the  motors  are  connected  with  trolley  and 
ground  and  the  whole  resistance  is  in  circuit  with  the  two 
motors  which  are  permanently  in  parallel.  The  remaining 
five  circular  contact  pieces  are  of  different  length.  The 
largest  of  them  is  the  second  from  the  bottom  and  the  small- 
est is  the  sixth  from  the  bottom.  These  middle  contacts 
have  the  purpose  of  cutting  out  portions  of  the  different  re- 
sistance from  the  motor  circuit.  When  the  controller  handle 
is  moved  to  the  second  notch  a  part  of  the  resistance  is  re- 
moved from  activity  by  the  second  contact  from  the  bottom. 
Turning  the  drum  to  notch  3,  the  third  segment  from  the 
bottom  of  the  drum  further  reduces  the  resistance.  Contin- 
uing by  turning  the  handle  to  notch  4  another  part  of  the 
resistance  is  cut  out  and  sending  the  handle  to  notch  5,  the 
last  part  of  the  resistance  is  cut  out  of  the  motor  circuit  by 
the  smallest  circular  contact.  At  this  position  the  motors 
receive  the  full  pressure  and  have  their  greatest  speed. 

When  the  car  is  at  rest  the  controller  handle  stands 
straight  back.  To  start  take  hold  of  it  with  the  left  hand 
and  push  it  to  the  left  in  the  direction  of  the  hands  of  the 
watch,  until  at  the  fifth  position,  it  meets  a  raised  part  on 
the  controller  cover  beyond  which  the  handle  cannot  pass. 
Turning  the  handle  as  described  will  send  the  car  ahead.  To 
back  up  the  car  or  to  run  it  backward,  the  handle  is  turned 
from  the  "off"  position  or  (position  of  rest  when  car  is 
standing  still)  to  the  right.  To  the  right,  there  are  the  same 
number  of  notches  and  speeds ;  the  only  difference  is  that  the 
direction  of  car  travel  is  reversed. 

Since  1893  an  improved  form  of  controller,  called  the 


103 

series-parallel  controller,  has  come  into  general  use.  The 
power  required  when  first  starting  a  car  with  the  motors  in 
series  is  only  one-fourth  what  it  would  be  with  the  same  mo- 
tors in  parallel  as  on  the  old  controllers  just  described.  Conse- 
quently in  the  modern  controller  the  motors  are  in  series 
as  in  Fig.  68,  on  the  first  few  points  of  the  controller,  and 
after  about  half  speed  has  been  reached  they  are  connected 
in  parallel  as  in  Fig.  69.  Hence  the  name,  series-parallel  con- 
troller. 

The  difference  between  the  old  method  and  the  new  is  that 
formerly,  to  reduce  the  pressure  at  the  motor  terminals  at 
the  start,  a  great  resistance  was  inserted  to  consume  a  part 
of  the  pressure  and  the  energy  thus  spent  in  the  resistance 
was  wasted.  In  the  new  way  the  two  motors  are  grouped  in 
series  first,  so  that  the  current  must  flow  through  one  motor 
before  it  gets  to  the  next  (Fig.  68),  and  therefore  but  one- 
half  the  pressure  can  reach  each  motor.  The  energy  passing 
through  the  first  motor  ( which  causes  the  reduction  in  press- 
ure for  the  other)  is  not  wasted,  as  it  is  doing  useful  work 
in  turning  the  armature  and  increasing  the  turning  moment 
necessary  for  starting  the  car. 

Practically  all  new  controllers  in  use  today  are  made  by 
the  General  Electric  Co.  and  these  controllers  are  divided 
into  four  classes,  as  follows : 

Type  B  controllers,  which  may  be  either  of  the  series  par- 
allel or  rheostatic  type  but  which  always  include  the  neces- 
sary contacts  and  connections  for  operating  electric  brakes. 

Type  K  controllers  is  the  series-parallel  type,  and  is  the 
type  almost  universally  used.  In  these  controllers  one  of 
the  features  is  the  shunting  or  short  circuiting  of  one  of  the 
motors  when  changing  from  the  series  to  the  parallel  con- 
nection. 

Type  L  controllers  are  also  of  the  series  parallel  type,  but 
differ  from  type  K  controllers  in  that  the  circuit  is  com- 


104 

pletely  opened  when  the  change  from  series  to  parallel  is 
made.  Type  R  controllers  are  of  the  rheostatic  type  and  are 
designed  to  control  one  or  more  motors  by  the  use  of  resist- 
ance only. 

One  of  the  most  important  features  of  the  General  Elec- 
tric controllers  is  the  magnetic  blow-out  by  means  of  which 
any  arc  forming  between  the  controller  terminals  is  blown 
out.  Other  important  features  are  the  cut-out  switches  and 
the  interlocks.  The  cut-out  switches  are  arranged  so  that 
either  motor  on  the  two-motor  equipments,  or  either  pair  of 
motors  on  the  four-motor  equipments,  may  be  cut  out  with- 
out impairing  the  operation  of  the  remaining  motors.  The 
interlocks  prevent,  as  far  as  possible,  the  abuse  of  the  con- 
troller, as  they  make  movement  of  any  of  the  handles  im- 
possible unless  the  'remaining  handles  are  in  such  a  position 
that  no  trouble  can  result.  These  controllers  are  built  with 
hinge  clamps,  permitting  the  cover  to  swing  open  from 
either  side,  or  to  be  completely  removed.  The  parts  of  all 
these  controllers  are  interchangeable,  permitting  ease  of 
repair  and  renewal. 

The  series  parallel  controllers  manufactured  at  the  present 
time  are  as  follows :  K-2,  capacity  two  4O-h.p.  motors,  5  se- 
ries and  4  parallel  points ;  K-4,  capacity  four  3o-h.p.  motors, 
5  series  and  4  parallel  points ;  K-6,  two-8o-h.p.  or  four-4O- 
h.p.  motors,  6  series  and  5  parallel  points;  K-io,  two  4o-h.p. 
motors,  5  series,  4  parallel  points;  K-n,  two  6o-h.p.  motors, 

5  series  and  4  parallel  points;  K-I2,  four  3O-h.p.  motors,  5 
series  and  4  parallel  points;  K-I3,  two  I25~h.p.  motors,  of 
series,  6  parallel  points ;  K-I4,  four  6o-h.p.  motors,  7  series, 

6  parallel  points ;  K-27,  two  6o-h.p.  motors,  4  series,  4  par- 
allel points ;  K-29,  four  4O-h.p.  motors,  6  series  and  5  paral- 
lel points;  K-3I,  four  3O-h.p.  motors,  4  series  and  4  parallel 
points;  K-32,  two  4O-h.p.  motors,  4  series  and  4  parallel 
points;  L-2,  two  175-h.p.  motors,  4  series    and  4  parallel 


105 

points;  L-3,  four  i5O-h.p.  motors,  8  series  and  7  parallel 
points ;  L-4,  four  xoo-h.p.  motors,  4  series,  4  parallel  points ; 
L~7,  four  2OO-h.p.  motors,  9  series,  and  6  parallel  points. 

The  electrical  brake  controllers  are  designated  by  the  letter 
B  and  are  as  follows : 

B-3,  capacity  two  4O-h.p.  motors,  4  series,  5  parallel  and  6 
brake  points ;  6-7,  two  looh.p.  motors,  6  series,  5  parallel 
and  6  brake  points;  B-8,  four  6oh.p.  motors,  6  series,  5 
parallel  and  /  brake  points;  6-13,  two  4O-h.p.  motors,  5  se- 
ries, 4  parallel  and  7  brake  points;  B-i8,  two  4O-h.p.  mo- 
tors, 4  series,  4  parallel  and  6  brake  points ;  6-19,  four  40- 
h.p.  motors,  5  series,  4  parallel,  7  brake  points ;  6-23,  two 
6o-h.p.  motors,  5  series,  4  parallel  and  7  brake  points;  6-29, 
iwo  6o-h.p.  motors,  5  series,  4  parallel  and  7  brake  points. 
The  latter  is  similar  to  6-23,  but  has  a  separate  brake  handle. 

The  rheostatic  controllers  are  designated  by  the  letter  R, 
and  are  made  in  the  following  capacities : 

R-n  controller,  capacity  one  5o-h.p.  motor,  6  controlling 
points ;  R-I4,  two  35~h.p.  motors,  5  points  ;  R-I5,  two  8o-h.p. 
motors,  6  points;  R-i6,  four  4O-h.p.  motors,  5  points;  R-I7, 
one  5o-h.p.  motor,  6  points;  R-ig,  two  5o-h.p.  motors,  6 
points;  R-22,  two  5o-h.p.  motors,  5  points;  R-29,  four  125- 
h.p.  motors,  6  points ;  R-37,  two  5o-h.p.  motors,  5  points ;  R- 
38,*two  35-h.p.  motors,  5  points ;  R-48,  four  75~h.p.  motors, 
8  points;  R~55,  iwo  i5o-h.p.  motors,  7  points. 

In  the  following  descriptions  of  controllers  there  is  in- 
cluded a  number  of  controllers  which  are  no  longer  manu- 
factured, but  many  of  these  older  controllers  are  still  to  be 
found  on  different  roads  where  the  old  equipments  have  not 
yet  been  discarded,  and  it  -was  therefore  deemed  advisable 
to  include  descriptions  of  the  old  as  well  as  the  modern  con- 
trollers. 

In  Fig  74  is  shown  the  type  K-2  controller  of  the  Gen- 
eral Electric  Company.  On  the  top  of  the  controller  are 


106 

visible  two  handles.  The  one  located  near  the  center  of 
the  controller  top,  called  the  controller  handle,  is  attached 
to  a  spindle  which  passes  through  the  whole  length  of  the 


FIG.  74. 

controller.  On  this  spindle  is  mounted  a  cylinder  by  means 
of  which  the  current  is  turned  on  to  the  motors.  The  sec- 
ond handle,  called  the  reversing  handle,  is  located  at  the 


107 

right  hand  side  and  its  purpose  is  to  control  the  direction  of 
the  car.  If  this  handle  is  pushed  forward  as  far  as  it  will 
go  the  car  will  go  ahead  when  the  controller  handle  is 
turned  to  close  the  circuit.  The  car  will  run  backward  when 
the  reversing  handle  has  been  pulled  to  the  other  extreme 
position  and  the  controller  handle  is  operated  as  before. 
What  takes  place  is  this :  The  reversing  lever  operates  a 
small  drum  inside  of  the  controller  which  is  provided  with 
contacts.  This  handle  has  three  positions.  The  working 
of  this  handle  forward  or  backward  changes  the  connections 
of  the  motor  armatures  so  that  the  current  flows  through 
them  in  one  direction  when  the  car  is  to  go  ahead,  and  in 
the  opposite  direction  when  the  car  is  to  go  backward,  as 
explained  in  the  previous  chapter.  When  the  reverse  handle 
stands  at  the  intermediate  position  between  forward 
and  reverse,  the  current  is  shut  off  from  the  motor 
at  that  controller  and  the  reversing  handle  can  be  removed 
only  when  it  is  at  this  intei  mediate  position.  An  interlock- 
ing arrangement  prevents  any  movement  of  the  reversing 
handle  except  when  the  large  or  power  cylinder  is  at  the 
"off"  position.  This  same  locking  device  prevents  any 
movement  of  the  power  cylinder  except  when  the  reversing 
handle  is  fully  thrown  into  proper  position  and  standing 
at  either  "forward"  or  "backward." 

The  reversing  cylinder,  therefore,  controls  the  direction 
in  which  the  car  moves.  The  propelling  of  the  car  and  its 
speed  is  controlled  by  the  controller  handle  with  which  the 
motorman  has  far  more  to  do  than  with  the  one  just  de- 
scribed. We  will,  therefore,  go  fully  into  the  details  of 
changes  that  take  place  when  the  controller  handle  is  shifted 
from  one  point  to  another. 

On  the  top  of  the  controller  will  be  seen  a  number  of 
points  or  dashes  and  on  the  spindle  is  fastened  a  finger  or 
index  which  points  to  these  raised  marks  as  the  handle  is 


<X  /?««*/«•  -totortM  ^crtM 

*****>~^ 

Armature  Armature 

-^mi^^^ 

S^r 


WWV^^ 


109 

moved  around  to  admit  current  to  the  motors.  When  the 
car  is  standing  ready  to  start,  the  finger  points  to  the  posi- 
tion marked  "off."  To  start  the  car,  the  handle  is  moved 
around  in  the  direction  of  the  hands  of  a  watch  to  the  first 
point.  This  connects  the  motors  and  resistance  to  the  cir- 
cuit so  that  the  current  flows  first  through  the  iron  plates 
of  the  resistance,  then  through  one  of  the  motors,  then 
through  the  other  motor,  and  finally  to  the  ground  through 
the  car  truck,  wheels  and  rails.  The  motors  are  in  this  case 
what  is  technically  known  as  connected  in  "series."  This 
is  represented  in  the  diagram  showing  the  connections  on 
the  first  point  in  Fig.  75.  The  connections  made  on  all  the 
following  points  of  this  controller  are  also  shown  in  the  same 
figure  and  should  be  studied  while  reading  this  explanation. 
On  the  second  point,  the  connections,  it  will  be  seen,  remain 
the  same  as  on  the  first,  except  that  two-thirds  of  the  re- 
sistance has  been  cut  out  of  the  circuit,  so  that  more  current 
may  reach  the  motors.  On  the  third  point,  eleven-twelfths 
of  the  resistance  is  cut  out  of  the  circuit  and  on  the  fourth 
point,  all  the  resistance  is  out  so  that  the  current  flows  only 
through  the  two  motors  in  series. 

All  resistance  is  now  cut  out  and  no  power  is  being 
wasted  as  the  current  is  doing  only  useful  work  in  the  mo- 
tors. We  can  therefore  keep  the  controller  on  this  point 
for  any  length  of  time  with  economy,  only  the  car  will  run 
a  little  less  than  half  its  maximum  speed.  To  increase  the 
speed  still  more,  we  move  the  controller  to  the  fifth  point. 
In  doing  this,  connections  are  made  so  that  part  of  the  cur- 
rent is  shunted  through  a  resistance  around  the  field  coils 
of  the  motor;  that  is,  instead  of  having  all  the  current  that 
flows  through  the  armatures  flow  also  through  the  fields,  a 
part  of  it  is  made  to  take  a  by-pass  or  shunt  around  the 
fields.  This  has  the  effect  of  increasing  the  speed  of  the 
motors  and  they  will  on  this  point  run  at  half  the  full  speed. 


110 

In  moving  the  controller  to  the  sixth  point,  an  important 
change  is  made  in  the  connections  of  the  motors. 

As  said  before,  when  the  controller  is  on  the  fourth  and 
fifth  points,  the  motors  are  in  series  with  each  other,  the 
current  flowing  first  through  one  and  then  through  the 
other.  Consequently  each  motor  gets  only  one-half  the 
pressure  of  voltage  between  the  trolley  wire  and  ground. 
That  is  to  say,  by  the  time  that  the  current  has  passed 
through  the  first  motor,  half  of  the  pressure  has  been  used, 
leaving  only  the  remaining  half  to  run  the  other  motor.  To 
increase  the  speed  we  must  now  connect  the  motors  so  that 
they  both  will  get  the  full  pressure  from  the  trolley  line. 
This  cannot  be  done  abruptly,  however,  but  some  resist- 
ance must  be  introduced  into  the  circuit  at  the  time  this 
change  is  made  to  prevent  the  car  from  jerking,  just  as  it 
would  have  acted  on  the  first  point  had  some  resistance  not 
been  interposed  when  first  starting.  Therefore,  on  the  sixth 
point,  the  motors  are  connected  so  that  the  current  divides 
and  half  flows  through  each  motor.  They  are  then  what 
is  technically  called  connected  in  "parallel."  They  both  get 
the  full  pressure,  except  that  some  resistance  is  put  in  the 
circuit  before  the  current  gets  to  the  motors.  A  part  of 
this  resistance  is  cut  out  on  the  seventh  point.  On  the  eighth 
point  all  of  the  resistance  is  out  and  the  motors  are  con- 
nected so  that  they  both  get  the  full  pressure  and  run  at 
nearly  full  speed.  On  the  ninth  point  part  of  the  current  is 
shunted  around  the  field  coils  as  on  the  fifth  point,  and  the 
motors  run  at  their  highest  speed.  At  each  point  there  is  pro- 
vided a  notch  on  a  wheel  or  ratchet,  mounted  on  the  con- 
troller spindle  inside  the  controller  case,  which  prevents  the 
handle  from  stopping  between  points  when  it  is  turned. 

At  the  lower  end  of  the  controller  are  located  the  motor 
cut-out  switches,  which  enables  one  to  operate  a  car  with  a 
single  motor  should  the  other  one  have  become  defective. 


Ill 


When  it  is  desired  to  have  both  motors  in  operation,  as  is 
generally  the  case,  both  switches  should  be  down.  The 
operator  will  find  an  instruction  card  in  each  controller  read- 
ing either — 


To  CUT  OUT  MOTOR  No.  I  (motor 

throw  up  left  hand  switch  as  far  as  it 
will  go. 

To  CUT  OUT  MOTOR  No.  2  Imotor 
nearest -HH-THE  OTHER  end  of  car 
throw  up  right  hand  switch  as  far  as  it 
will  go. 


To  CUT  OUT  MOTOR  No.  I  Imotor 
nearest  ••  THE  OTHER  end  of  can 
throw  up  left  hand  switch  as  far  as  it 
will  go. 

To  CUT  OUT  MOTOR  No.  2  (motor 

throw  up  right  hand  switch  as  far  as  it 
will  go. 


It  will  be  noticed  that  they  do  not  read  alike  on  the  two 
controllers  of  the  same  car.  This  is  due  to  the  difference  in 
connection.  Should  at  any  time  it  become  necessary  to  cut 
out  a  motor,  look  for  the  instruction  card  in  the  controller 
stand.  To  operate  with  a  single  motor,  the  car  will  start  on 
point  I  and  reach  its  full  speed  on  point  5.  A  stop  is  placed 
on  the  controller  spindle,  with  which  a  pin  engages,  pre- 
venting movement  of  the  controller  cylinder  beyond  the 
fifth  point.  This  is  effected  by  either  of  these  cut-out 
switches,  which,  in  being  raised,  operate  the  pin. 

The  high  controlling  lever  on  the  top  (Fig.  74)  turns  the 
central  shaft,  on  which  are  mounted  the  contact  pieces  or  sec- 
tions, which,  when  the  shaft  is  turned,  will  establish  connec- 
tions with  the  stationary  terminals  located  to  the  left. 

The  wires  to  the  left  connect  with  the  terminal  board  in 
the  controller  to  which  are  also  attached  the  wires  going  to 
the  motors  and  to  the  second  controller  and  resistance  boxes. 

The  old  K  controller  of  the  General  Electric  Co.  is  very 
similar  to  the  K-2.  It  was  of  earlier  construction  than  the 
K-2,  but  as  the  K-2  has  been  most  widely  used,  it  was  con- 
sidered best  to  give  it  the  more  detailed  description.  The  K 


controller  is  about  2  in.  shorter  than  the  K-2  and  its  appear- 
ance is  almost  the  same.  It  has,  however,  two  points  less ;  in 
other  respects  its  mechanical  contruction  is  the  same. 


FIG.  76. 


The  old  style   or  rheostat   controllers  of  this  company, 
known  as  types  51  and  83,  ?nd  described  in  the  first  part  of 


113 


this  chapter,  have  been  gradually  superseded  by  the  R  type 
of  controllers  previously  mentioned.    A  controller   of  this 
type  R-I7,  is  shown  in  Fig.  76. 
The  K-4  controller  is  used  in  connection  with  larger  cars, 


where  four  motors  instead  of  two  are  mounted  on  the 
trucks.  Its  action  is  like  the  K-2  controller,  and  the  differ- 
ence is  that  instead  of  having  first  two  motors  in  series  and 
later  in  parallel,  as  there  are  in  this  case,  two  identical  sets 


114 

of  motors  of  two  motors  per  set.  Each  set  of  two  motors 
is  permanently  grouped  in  parallel,  and  the  one  pair  is  first 
placed  in  series  with  the  other  pair  or  set,  and  finally  the  two 
series  are  connected  in  parallel. 


The  old  K-2i  controller  is  the  same  as  the  K-2,  except  that 
it  is  of  greater  capacity,  as  its  contacts  and  wires  are  larger. 

The  K-6  controller  which  is  designed  for  two  8o-h.p.  mo- 
tors or  four  4O-h.  p.  motors  is  shown  in  Fig.  77. 


115 

The  K-io  controller  is  designed  for  two  4O-h.  p.  motors. 
It  is  a  controller  with  nine  notches.  On  the  first  four  notches 
'the  motors  are  in  series  and  resistance  in  circuit.  On  the 
fifth  notch  motors  are  in  series  with  resistance  all  cut  out. 
On  the  sixth,  seventh  and  eighth,  motors  are  in  parallel  and 
resistance  in  circuit.  The  ninth  is  for  full  speed,  motors  in 
multiple.  The  K-io  controller  .is  shown  in  Fig.  78.  Field 
shunts  are  not  used  with  this  controller, 

The  K-n  controller  is  the  same  as  the  K-io,  except  it  is 
designed  for  heavier  currents  and  larger  motors. 

The  K-I2  controller  is  like  the  K-n,  except  that  it  is  made 
to  operate  four  motors  in  two  sets  just  as  the  K-4. 

The  K-I3  is  designed  for  two  125-!!.  p.  motors.  It  is  a 
thirteen  notch  controller.  The  motors  are  in  series  up  to 
and  on  the  seventh  point.  From  the  eighth  to  the  thir- 
teenth they  are  in  multiple.  The  preferred  running  notches 
dre  the  seventh  and  thirteenth.  No  field  shunts  are  used. 

The  K-I4  is  for  four  6o-h.  p.  motors  and  is  like  the  K-I3, 
except  that  it  handles  four  motors  in  two  groups  as  the  K-4. 

The  old  K- 1 5  controller  is  practically  a  double  K-I3,  with 
two  controlling  drums  and  t\\o  125-!!.  p.  motors  controlled 
by  each  drum.  The  notches  are  the  same  as  on  the  K-I3. 

The  old  K-i6  controller  is  the  same  as  K-15,  but  with  dif- 
ferent case. 

The  K-27  controller  is  similar  to  the  K-n.  but  is  arranged 
for  operation  on  a  metallic  circuit,  having  contacts  for  open- 
ing both  sides  of  the  circuit. 

The  K-29  controller  is  similar  to  the  K-6,  but  has  contacts, 
for  opening  both  sides  of  the  circuit. 

The  K-3i  controller  is  similar  to  the  K-27,  but  has  re- 
verse switch  arranged  for  four  motors. 

The  K-32  controller  is  also  similar  to  the  K-27,  but  is  of 
smaller  capacity. 

The  L-2  controller  is  used  for  two  I75~h.  p  motors,  and 


116 

the  L-4  for  four  loo-h.  p.  motors.  They  have  four  points  in 
series  and  four  in  multiple.  The  handle  is  operated  con- 
trary to  the  hands  of  a  watch,  or  in  the  opposite  direction 


from  most  controllers.  The  first  half  revolution  moves  the 
controller  through  the  series  points  and  brings  them  into 
full  series.  To  throw  them  into  multiple  the  movement  of 
the  handle  of  the  controller  Is  continued  on  around  to  the 


117 

original  off  position,  and  when  the  handle  begins  to  pass 
over  what  were  the  series  notches  on  the  first  revolution, 
the  motors  are  thrown  in  multiple,  so  that  when  the  handle 
has  completed  a  revolution  and  a  half  the  motors  are  con- 
nected for  full  speed  in  multiple.  The  current  is  always  off 
when  the  handle  is  at  the  left  and  always  on  when  it  is  at 
the  right.  A  brass  dial  on  top  of  the  controller  indicates 
whether  the  motors  are  in  series  or  multiple. 

The  L-3  controller  for  four  150-!!.  p.  motors  has  15  points, 
eight  series  and  seven  parallel.  This  controller  is  shown  in 

Fig-  79- 

The  L-J  controller  for  four  2oo-h.  p.  motors  has  15  points, 
nine  series  and  six  parallel. 

The  General  Electric  Company's  controllers  for  use  with 
electric  brakes  are  known  as  the  B  type.  The  action  of  the 
electric  brake  and  the  way  to  operate  it  is  described  later  on 
in  the  chapter  on  brakes.  Some  of  these  controllers  have  a 
double  set  of  points  or  notches.  Moving  the  handle  in  the 
usual  way  from  off  position  starts  the  car  just  as  on  other 
controllers.  Moving  the  handle  the  other  way  from  off  po- 
sition applies  the  electric  brake,  if  the  car  is  running.  The 
capacities  of  the  B  controllers  at  present  manufactured  and 
the  number  of  controlling  points  on  each  has  been  already 
shown  in  this  chapter.  The  B-8  controller  has  separate  han- 
dles for  power  and  brake  as  is  also  the  case  with  the  6-7, 
B-iQ  and  the  6-29. 

The  6-23  controller  is  shown  in  Fig.  80,  and  has  but  one 
power  and  brake  handle.  The  6-3,  6-13  and  B-i8  also  have 
only  one  handle  which  is  operated  in  one  direction  for  the 
power  and  in  the  other  direction  for  the  brake,  as  just  de- 
scribed. Of  the  B  controllers  the  6-13  is  most  generally 
used  and  its  braking  connections  are  such  as  to  render  the 
skidding  of  the  wheels  practically  impossible. 

The  Westinghouse  Klectric  &  Manufacturing  Co.  former- 


118 


ly  manufactured  controllers  of  which  a  number  was  of  the 
series-parallel  type.  The  Westinghouse  controllers  are  no 
longer  made,  but  as  many  of  them  will  be  found  in  use  on 


FIG.  80. 


different  roads,  a  description  of  them  is  given.  The  old  West- 
inghouse series-parallel  controllers  and  their  coresponding 
diverters  are  known  as— 


119 

Controllers  Diverters 

G.  E. 

No.  14  No.    7 

No.  28  No.  46 

No.  28A  No.  46  or  47 

No.  29  No.  47 

No.  38  No.  38 

With  the  rapid  advancement  and  development  of  electric 
street  railroads  more  powerful  motors  were  required,  and 
at  the  same  time  greater  economy  in  consumption  of  power 
was  the  object  aimed  at  by  the  manufacturers.  Owing  to 
these  developments  and  advancements  the  parallel  controller 
D,  described  at  the  beginning  of  the  chapter,  has  not  been 
manufactured  for  several  years. 

In  the  center  of  the  G  controller  cover  plate  is  located  the 
controller  handle  for  regulating  the  speed  of  the  car.  On 
the  right-hand  side,  through  the  rim  of  the  cover  plate,  ex- 
tends a  straight  handle  or  lever,  which  is  the  reversing 
handle.  The  two  raised  lugs  to  the  left  on  the  cover  are 
stops  which  prevent  the  controller  lever  from  going  round 
to  make  a  complete  circle.  At  the  front  lug  the  handle  is  at 
the  "off"  position.  The  cylinder  contacts  are  disconnected 
from  the  contact  fingers  in  this  position  and  the  car  is  at 
rest.  When  the  handle  is  turned  so  far  as  to  strike  the 
other  lug  the  highet  speed  is  reached.  The  reverse  handle, 
which  should  be  moved  only  when  the  controller  handle  is 
in  the  "off"  position,  has  three  notches.  The  central  posi- 
tion opens  the  circuit  and  cuts  off  the  current ;  the  outward 
and  the  inward  position  control  the  direction  in  which  the 
car  travels,  either  forward  or  back.  If  the  handle  is  pushed 
forward  as  far  as  possible,  the  car  will  go  ahead  when  .the 
current  is  turned  on  by  the  controller  handle.  Pulling  the 
handle  inward  (toward  one's  self  or  toward  the  car)  re- 


120 

verses  the  armature  connections,  so  that  the  car  backs  or 
run  backward  when  the  controller  handle  is  moved  from 
the  "off"  position  to  the  first  notch.  The  contacts  con- 
trolled by  this  reversing  handle  are  mounted  on  a  small 
vulcabeston  disk  which  is  secured  in  the  inside  of  the  con- 
troller cover.  All  the  terminals  and  contact  fingers,  as  well 
as  the  rings  on  the  drum,  are  separated  from  one  another  by 
vulcabeston  partitions  which  project  between  them  and  the 
rings.  Their  object  is  to  prevent  the  current  from  jumping 
from  one  terminal  to  the  next. 

The  first  G  controllers  had  ratchet  wheels  with  10  notches. 
Only  the  first  three  notches  or  controller  positions  and  the 
last  three  are  "running"  positions  (namely,  the  positions  in 
which  the  controller  handle  may  remain  for  some  time  to 
operate  the  car),  while  the  other  four  should  be  passed  over 
slowly,  but  without  stopping  on  any  one  of  them  for  more 
than  a  moment. 

In  the  later  G  controllers,  the  ratchet  wheels  had  only  the 
six  running  notches,  the  intermediate  four  being  omitted. 
The  changes  that  take  place  on  the  various  positions  are 
enumerated  below  and  may  be  readily  followed  by  the  dia- 
gram shown  in  Fig.  81.  The  reversing  handle  being  in  the 
forward  position,  the  car  will  go  ahead  when  the  controller 
handle  is  operated.  Moving  the  controller  handle  from  the 
"off"  position  to  the  first  notch  will  close  the  circuit  and 
connect  the  controllers,  motors  and  diverter  resistance  to 
the  trolley  line  and  to  the  ground  return  or  rail.  Both  mo- 
tors are  then  in  series  connections  with  one  another  and  also 
in  series  with  the  whole  diverter  resistance.  This-is  the  start- 
ing position ;  the  mtors  receive  each  less  than  half  the  pres- 
sure o'f  the  line.  This  slow  speed  can  be  used  especially  in 
crowded  streets.  Moving  the  controller  handle  to  the  sec- 
ond notch  has  the  effect  of  short  circuiting  or  cutting  out  of 
active  service  one-half  of  the  diverter  resistance.  This  allows 


121 


a  heavier  current  to  flow  through  the  motors,  resulting  in 
increased  speed. 

Moving  controller  handle  to  the  third  notch  causes  the 
controller  drum  to  cut  out  all  the  resistance,  and  now  the 


Motor  No!  Motor  N&2 


^ — \MAM/vV^^ 

^-^w^^ 

\MQ//MM3^^^ 

^ym~- 


two  motors  are  in  series  with  one  another  and  receive  the 
total  voltage  of  the  line.  Each  one  is  working  under  half 
the  total  pressure.  The  position  is  an  economical  one  and 
the  speed  is  half  full  speed.  The  controller  may  remain  in 


122 

this  position  for  any  length  of  time.  Between  the  third  and 
fourth  notches  several  intermediate  connections  are  made 
between  the  diverter  and  motors.  However,  as  these  are 
made  in  succession  and  without  stopping,  and  are  not  opei- 
ating  positions,  they  are  omitted  from  the  ratchet,  and  when 
the  handle  arrives  at  the  fourth  notch  both  motors  have 
changed  from  the  series  to  the  parallel  connection,  and  the 
diverter  resistance  is  in  series  circuit  with  one  of  them.  This 
is  the  next  higher  speed.  In  the  fifth  notch  half  of  the  di- 
verter resistance  is  cut  out,  but  the  relations  of  the  motors 
is  unchanged.  The  speed  is  further  increased.  Neither  the 
fourth  nor  the  fifth  notch  should  be  used  for  any  great 
length  of  time.  In  the  sixth  position,  at  which  the  motors 
reach  their  highest  speed,  all  resistance  is  cut  out  of  the  cir- 
cuit and  both  motors  are  in  parallel,  each  receiving  the  full 
pressure  of  the  line. 

The  No.  14  Westinghouse  controller  is  in  outward  appear- 
ance very  similar  to  the  G  controller.  It  has,  however,  a 
number  of  modifications  which  should  be  noted.  The  con- 
troller drum  is  mounted  so  to  swing  outward,  for  the  pur- 
pose of  easily  examining  or  to  have  access  to  all  parts,  as  in 
the  G  controller.  Further,  there  is  provided  an  interlocking 
device  between  the  controller  and  the  reversing  device.  To  re- 
move either  it  is  necessary  to  bring  the  handle  to  the  "off" 
position,  namely,  into  that  position  in  which  the  current  is  cut 
off  from  the  trolley.  Lastly,  this  controller  is  provided 
further  with  motor  cut-out  switches  or  plugs.  It  was  at 
first  the  custom  of  the  Westinghouse  company  to  place  the 
motor  cut-outs  under  the  seats  in  the  car.  This  method  was 
later  abandoned,  and  plugs  were  provided  inside  of  the  con- 
troller casting  on  the  right-hand  side.  The  various  changes 
made  with  this  controller  will  be  given  in  a  short  and  con- 
cise way.  The  changes  are  more  gradual  and  the  work  is 
more  evenly  distributed  than  with  the  G  controller.  In  prin- 


123 

ciple  it  is  very  similar  to  the  operation  of  the  G  controller, 
and  therefore  it  is  believed  that  with  this  controller,  and  all 
the  following  that  are  described  of  the  Westinghouse  make, 
the  simple  enumeration  of  the  change  will  suffice.  In  this 
controller  the  reversing  switch  changes  the  connections  of 
the  motor  field  coils  to  cause  the  armature  to  rotate  in  the 
opposite  direction. 

Moving  the  controller  handle  from  the  "off"  position  to 
notch  i,  both  motors  are  connected  in  series  with  one  another 
and  in  series  with  all  the  diverter  resistance  between  trolley 
and  rail.  This  is  the  starting  position  and  slowest  speed. 

On  notch  2  both  motors  are  in  series  with  each  other  and 
the  diverter  resistance,  with  some  of  the  resistance  short 
circuited,  causing  an  increased  current  to  pass  the  motors 
and  resulting  in  higher  speed. 

Notch  3.  The  whole  resistance  is  cut  out  of  action  and 
the  two  motors,  still  in  series  with  one  another,  are  receiv- 
ing the  total  line  pressure,  that  is,  each  one  receives  half  of 
this  pressure.  The  cutting  out  of  all  the  resistance  further 
increases  the  motor  speed. 

Notch  4.  Between  notch  3  and  4  there  are  a  number  of 
intermediate  combinations  which  follow  in  rapid  succession, 
and  when  contact  is  established  in  notch  4  the  motors  are 
no  longer  in  series.  Each  motor  is  in  series  with  half  of  the 
resistance,  and  one  motor  and  resistance  are  grouped  in  par- 
allel with  the  other  one  and  resistance,  resulting  in  increase 
of  speed  over  notch  3. 

Notch  5.  The  resistance  is  cut  out  of  circuit  of  one  of  the 
motors  which  receives  the  total  line  pressure.  It  remains 
in  parallel  with  the  other  motor  which  has  still  half  of  the  re- 
sistance in  series  with  it.  Speed  in  this  notch  is  higher  than 
on  notch  4. 

Notch  6.  The  resistance  is  also  cut  out  of  the  circuit  of 
the  second  motor,  therefore  no  resistance  is  in  the  circuit. 


124 

The  motors  are  in  parallel,  each  receiving  the  full  line  pres- 
sure, resulting  in  maximum  speed. 

If  at  any  time  it  becomes  necessary  to  cut  out  one  of  the 
motors,  the  upper  plug  will  cut  out  motor  number  i,  the 
lower  plug  motor  number  2.  Running  with  the  one  motor 
only  the  car  will  not  start  when  controller  is  moved  to  notch 
i,  but  it  has  to  be  placed  on  notch  4,  which  is  the  starting 
position  under  these  conditions. 

The  Nos.  28  and  29  Westinghouse  controllers  are  both 
similar  in  construction  and  operation  to  the  No.  14.  The 
difference  is  mainly  of  a  mechanical  nature.  The  No.  28  is 
of  smaller  dimensions  than  the  No.  14,  while  the  No.  29  is 
built  heavier,  to  control  more  powerful  motors  and  cur- 
rents. The  grouping  of  the  circuits  by  these  controllers  is 
very  similar  to  that  of  the  No.  14.  The  main  difference  is 
that  the  resistance  is  not  divided  between  the  two  motors, 
and  any  change  made  in  it  affects  both  motors  exactly  the 
same  way. 

Notch  I.  Motor  No.  i,  motor  No.  2  and  diverter  all  in 
series. 

Notch  2.  Motor  No.  i,  motor  No.  2  and  part  of  resist- 
ance in  series. 

Notch  3.  Motor  No.  i,  motor  No.  2,  in  series,  resistance 
all  out  of  action. 

Notch  4.  Motor  No.  i,  motor  No.  2,  in  parellel,  resist- 
ance in  series  with  both  of  them. 

Notch  5.  Motor  No.  i,  motor  No.  2,  in  parallel,  part  of 
diverter  cut-out,  rest  in  series  with  both  motors. 

Notch  6.  Motor  No.  i,  motor  No.  2,  in  parallel  between 
the  line  receiving  full  pressure,  all  resistance  being  cut  out. 
Highest  speed  obtainable. 

When  but  one  motor  is  used  the  car  will  not  start  before 
the  fourth  notch  is  reached. 

The  28A  Westinghouse   controller  is  heavier  in   all   its 


125 

parts  and  had  many  changes  of  a  mechanical  nature.  To 
begin  with,  the  reversing  handle  as  well  as  the  controller 
handle  was  placed  on  top  of  the  controller  cover.  They  were 
made  to  interlock  to  prevent  the  moving  of  the  reversing 
handle  when  the  controller  handle  is  not  in  the  "off"  po- 
sition. This  controller  has  seven  notches  or  running  posi- 
tios,  and  in  case  that  one  of  the  motors  is  cut  out,  the  car 
will  start  with  the  first  notch  and  reach  maximum  speed 
in  the  fourth  position,  beyond  which  the  handle  will  not 
turn.  A  latch  is  provided  which  automatically  locks  the 
drum  when  either  one  of  the  motor  cut-out  plugs  at  the 
lower  right-hand  side  of  the  controller  is  removed.  The 
controller  changes  are  as  follows : 

Notch  i.  Motor  i,  motor  2  and  total  resistance  in  series 
with  one  another. 

Notch  2.  Motor  i,  and  motor  2,  in  series  with  less  re- 
sistance. 

Notch  3.    Same  as  2,  with  still  less  resistance. 

Notch  4.   Motors  i  and  2,  in  series  without  resistance. 

Notch  5.  Motors  i  and  2,  in  parallel  with  part  of  resist- 
ance in  series. 

Notch  6.    Motors  i  and  2,  in  parallel  with  less  resistance. 

Notch  7.  Motors  i  and  2,  in  parallel  without  any  resist- 
ance. 

The  Westinghouse  No.  38  controller  was  designed  for 
large  cars  and  motors.  Its  general  arrangement  is  like  No. 
28A  as  to  interlocking  of  controller  and  reversing  handles 
as  well  as  motor  cut-out  switches,  and  it  was  the  largest  con- 
troller for  this  service.  Only  the  controllers  used  for  loco- 
motives are  larger  and  heavier  as  regards  the  internal  parts. 
It  has  four  more  contact  rings  than  the  14,  28,  28 A  and  29. 
There  are  eight  notches  or  positions  for  the  controller  handle. 

Notch  i.  Motors  in  series  with  one  another  and  full  re- 
sistance. 


126 

Notch  2.     Conditions  as  before,  but  with  less  resistance. 

Notch  3.  Motors  as  before,  with  still  less  resistance  in 
series. 

Notch  4.  The  two  motors  in  series,  resistance  entirely  cut 
out. 

Notch  5.  Motors  in  parallel,  with  a  part  of  the  diverter 
resistance  in  series  with  both  motors. 

Notch  6.  Motors  as  on  5,  some  resistance  cut  out. 

Notch  7.  Motors  as  on  6  and  some  more  resistance  cut 
out. 

Notch  8.  Motors  in  parallel  as  on  7  and  all  resistance  cut 
out.  Maximum  speed. 

When  one  of  the  motors  is  cut  out  of  circuit  and  the  car 
is  operated  by  the  other,  it  will  start  when  controller  handle 
is  moved  into  the  first  notch  and  reaches  maximum  speed 
in  the  fourth. 

The  diverter  box  is  the  same  as  a  resistance  box.  It  is 
made  of  iron  bands  wound  into  flat  iron  coils  of  spiral  shape, 
separated  by  mica.  They  must  be  of  different  sizes  depend- 
ing on  the  capacity  of  the  motors.  The  heavier  the  current 
that  is  supplied  to  a  motor,  the  wider  has  to  be  the  iron 
spiral,  to  prevent  overheating. 

The  Walker  Company's  Controllers.— The  Walker  Com- 
pany had  a  number  of  controllers  on  the  market,  but  few,  if 
any,  of  these  will  be  found  in  use  at  present.  One  is  the 
J  type.  The  reversing  handle  is  at  the  right.  In  this 
controller  there  are  no  separate  switches  or  plugs  provided 
for  cutting  out  any  one  motor,  these  provisions  being  made 
on  the  reversing  cylinder,  so  that  this  one  handle  can  ac- 
complish all  these  functions,  as  will  be  described  later  on. 
The  controller  has  five  running  notches,  and  the  resistance 
is  of  such  capacity  that  any  one  of  these  notches  may  be 
used  for  continuous  service,  though  not  with  economy.  An- 
other point  in  construction  to  be  mentioned  is  that  the  con- 


127 


troller  is  provided  with  a  magnetic  lock,  which  renders  it 
impossible  to  move  the  reverse  handle  when  current  is 
flowing  through  the  controller.  The  construction  is  such 
that  when  the  circuit  is  opened  contact  is  broken  simul- 


Troneu 
y 


Motor  No  I  Motor,  Nti 


^^^^ 


taneously  at  eight  different  places,  thereby  greatly  over- 
coming the  bad  arc  that  otherwise  would  exist  if  it  was 
broken  at  one  or  two  places  only.  In  this  controller,  as  in 
all  others,  every  terminal  is  lettered  so  as  to  prevent  confu- 
sion. These  letters  are  for  the  benefit  of  the  electrician  or 
wireman  who  wires  the  cars,  se'.s  up  the  motors  and  makes 
the  connections. 


128 

The  combinations  with  this  controller  are  as  follows  (see 
Fig.  82)  : 

First  point.    Motors  in  series ;  all  the  resistance  in  circuit. 

Second  point.  Motors  in  series  and  the  current  only  flow- 
ing through  one-half  the  rheostat. 

Third  point.  The  two  motors  are  in  series  with  the  rheo- 
stat entirely  cut  out. 

Fourth  point.  The  current  now  flows  from  the  trolley  to 
the  center  of  the  rheostat,  and  is  equally  divided  between 
the  two  motors,  which  are  in  parallel. 

Fifth  point.     Motors  in  parallel,  resistance  all  out. 

There  are  six  positions  of  the  reverse  cylinder.  In  the 
normal  "off"  position  the  handle  of  the  reverse  cylinder 
stands  parallel  with  the  face  of  the  controller,  pointing  to 
the  right.  In  this  position  both  motors  are  cut  out.  If  now 
the  handle  is  pushed  forward  until  it  comes  in  contact  with 
the  stop,  both  motors  are  connected  so  as  to  carry  the  car 
forward.  If  the  handle  is  pulled  backward  until  it  comes  in 
contact  with  the  stop,  both  motors  are  connected  in  such  a 
direction  as  to  carry  the  car  backwards.  To  cut  out  one 
motor,  raise  the  reverse  handle  about  ^  in.,  far  enough  to 
clear  the  stop  and  turn  the  cylinder  until  the  handle  points 
to  the  left.  If  it  is  now  pushed  forward  against  the  stop, 
so  as  to  cover  the  point  marked  "i,"  No.  I  motor  only  is 
in  action  propelling  the  car  forward,  while  No.  2  motor  is 
cut  out.  Pull  the  reverse  handle  back  about  45°,  or  an 
eighth  of  a  turn,  until  it  covers  point  marked  "2,"  and  No.  2 
motor  only  is  in  action,  carrying  the  car  forward,  while  No. 
i  motor  is  cut  out.  Pulling  it  still  farther  back  until  it  comes 
in  contact  with  the  stop  and  covers  point  marked  "i,"  we 
have  again  No.  i  motor  in  action,  carrying  the  car  back- 
wards. Moving  it  forward  from  here  about  45°  until  it 
covers  the  other  point  marked  "2,"  we  have  again  No.  2 
vnotor  in  action,  carrying  the  car  backwards. 


129 


These  combinations  give  us,  therefore,  on  the  controller 
one  forward  point  for  both  motors,  one  for  No.  I  and  one 
for  No.  2,  and  the  three  reverse  positions  corresponding  to 
these.  In  running  on  No.  i  motor  alone,  either  forward  or 
back,  the  car  does  not  "take  power"  until  the  controller 
handle  reaches  the  fourth  point.  With  No.  I  motor  the  car 
"takes  power"  between  the  third  and  fourth  points. 

The  last  controller  made  by  the  Walker  Company  was 
the  type  S.  In  this  car  controller  a  solenoid  or  coil  of  wire 


is  used  between  each  contact  ring.  This  is  to  prevent  the 
burning  of  the  contact  rings  and  fingers  by  the  electric  arc 
which  forms  when  a  circuit  is  opened.  The  magnetism 
caused  by  the  solenoid  or  coil  blows  out  the  arcs  as  soon  as 
they  form.  Fig.  83  shows  the  plan  of  this  controller  top 
with  the  handles  at  "off"  position.  It  will  be  seen  that  there 
are  seven  points  on  this  controller.  On  the  first  four  the 
motors  are  in  series  and  on  the  last  three  in  parallel. 

The  reverse  lever  on  this  controller  differs  from  that  on 
other  controllers  in  several  respects  Looking  at  the  sur- 
face plate  diagram,  Fig.  83,  we  see  the  various  reverse  lever 


130 

points  indicated  around  the  reverse  lever  at  the  right.  The 
point  marked  No.  i  ahead  means  that  when  the  reverse 
lever  is  put  over  to  that  point,  motor  No.  i  will  run  the  car 
ahead,  No.  2  being  cut  out,  and  so  on  for  the  other  points. 
The  position  marked  A  means  that  on  this  both  motors  will 
act  together  to  drive  the  car  ahead,  while  R  means  that 
both  motors  will  reverse.  The  other  points  will  explain 
themselves,  all  but  the  one  marked  "Emerg.,"  which  is  an 
emergency  electric  brake  for  stopping  the  car  quickly  in 
emergencies  in  place  of  reversing  it.  All  that  is  necessary 
to  do  to  operate  this  brake  is  to  shut  off  current  with  the 
controller  handle  and  then  put  the  reverse  handle  on  the 
emergency  brake  position.  After  this  is  done  begin  to 
apply  the  hand  brake.  The  emergency  electric  brake  acts 
by  turning  the  motors  into  dynamos  by  changing  their  con- 
nections and  causing  them  to  generate  current  to  stop  them- 
selves. 

Controller  of  the  Steel  Motor  Company. — This  company 
has  built  various  controllers  since  1892.  The  last  and  most 
improved  type  is  known  as  the  43  controller.  It  was  made 
very  simple  by  reducing  the  number  of  terminals  and  connec- 
tions. This  controller  differed  from  others  in  that  wires 
from  the  car  cables  did  not  go  to  a  terminal  board,  but  in- 
stead directly  to  the  contact  fingers  of  the  controller. 

Arcing  at  the  opening  of  the  circuit  it  subdued  by  pro- 
viding two  coils  placed  on  either  side  of  the  controlling 
cylinder  or  drum  and  partially  enveloping  it,  the  drum  act- 
ing as  the  core  of  an  electro  magnet.  The  current  passes 
through  the  coils  before  a  connection  is  made  with  the 
motors. 

The  reverse  and  cut-out  switches  are  combined.  An  in- 
dex shows  the  positions  to  which  the  reverse  handle  is 
moved  in  order  to  run  both  motors  together  or  either  of 
them  independently  in  either  direction.  The  reverse  handle 


131 

cannot  be  removed  except  when  the  circuit  is  open.  In  or- 
dinary practice  the  motors  can  be  reversed  without  shutting 
off  the  current,  but  the  cam  index  on  the  inside  is  so  de- 
signed that  the  addition  of  a  common  iron  washer  provides 
the  necessary  device  to  prevent  this.  There  are  nine  points 
of  contact,  and  when  used  without  a  shunt  across  the  fields, 


two  of  them  are  running  positions ;  when  used  with  a  shunt, 
there  are  three  running  positions. 

At  "off"  position  the  controller  handle  is  at  about  the 
same  place  as  on  other  series-parallel  controllers,  and  to 
start  the  car  it  is  moved  clock-wise.  The  connections  made 
are  as  follows : 

First  point.  Motors  are  in  series  with  all  resistance  in 
circuit. 

Second  point.  Motors  in  series,  about  two-thirds  of  the 
resistance  in  circuit. 

Third  point.  Motors  in  series,  about  one-third  of  resist- 
ance in  circuit. 


132 

Fourth  point.  Motors  in  series  with  all  resistance  cut  out. 
After  passing  fourth  contact,  circuit  is  broken  and  both 
motors  are  put  in  multiple. 

Fifth  point.  Motors  in  multiple  with  full  resistance  in 
series  circuit  with  them. 

Sixth  point.  Motors  in  multiple  with  two-thirds  of  re- 
sistance in  series  with  both  motors. 

Seventh  point.  Motors  in  multiple  with  one-third  of  re- 
sistance in  series  with  them. 

Eighth  point.    Motors  in  multiple,  no  resistance. 

Ninth  point.  If  motors  are  operated  with  a  shunt  this  is 
brought  into  service  on  the  ninth  contact.  If  no  shunt  is 
used  the  ninth  point  does  not  produce  any  change  over 
point  8,  and  operates  the  motors  in  precisely  the  same  man- 
ner as  the  eighth. 

The  effect  produced  by  each  notch  of  the  reverse  and 
cut-out  switch  is  indicated  by  the  copy  of  the  index  around 
the  reverse  switch  shown  in  Fig.  84. 


CHAPTER   IV. 

MULTIPLE   UNIT   SYSTEMS. 

In  the  previous  chapter  was  explained  the  method  of  con- 
trolling motor  cars  when  run  singly  or  when  towing  one  or 
more  trail  cars  not  equipped  with  motors.  On  some  electric 
railways  where  the  traffic  is  heavy  it  becomes  necessary  to 
run  trains  of  several  cars,  some  or  all  of  which  are  motor 
cars.  It  also  becomes  necessary  at  times  to  divide  these 
trains  into  smaller  ones  or  to  add  more  cars  as  the  traffic 
fluctuates,  and  as  it  is  obviously  unpractical  to  have  more 
than  one  motorman  to  drive  a  train  means  must  be  provided 
so  that  each  motor  car  of  the  train  may  be  controlled  from 
the  front  of  the  train  by  one  man.  This  method  of  control  is 
generally  known  as  the  multiple  unit  system  of  control.  One 
of  these  multiple  controllers  is  placed  at  each  end  of  each 
motor  car  and  they  are  so  arranged  that  when  the  controller 
at  the  front  end  of  the  train  is  moved  to  any  particular  notch, 
all  the  other  controllers  on  the  train  are  automatically  moved 
to  the  same  position,  so  that  while  the  train  is  operated  as  a 
whole  from  one  controller  each  car  is  operated  independently 
by  its  own  controller.  The  multiple  unit  system  allows  the 
greatest  flexibility  in  the  operation  of  cars,  for  one  car  can 
be  run  alone  or  any  number  of  cars  may  be  coupled  together, 
each  car  being  driven  by  its  own  motor  as  an  independent 
unit. 

Owing  to  the  large  amount  of  current  required  to  operate 
electric  cars  the  multiple  unit  system  is  generally  operated 
on  the  third  rail  system  described  in  Chapter  VI.  The  con- 


134 

tact  area  of  the  ordinary  trolley  wheel  with  the  trolley  wire  is 
too  small  to  carry  the  current  required  for  a  heavy  train  of 
cars  and  as  the  use  of  several  trolleys  on  one  train  would  be 
too  troublesome,  the  current  is  taken  from  a  third  rail  along- 
side the  track,  by  means  of  sliding  contacts  or  shoes  carried 
on  each  car.  There  are  two  systems  of  multiple  control  in 
use,  that  of  the  General  Electric  Co.,  known  as  the  type  M 
control,  which  is  electrically  operated,  and  the  Westinghouse 
multiple  control  system  which  is  operated  by  means  of  com- 
pressed air. 

In  the  type  M  control  the  series  parallel  motor  controller 
as  described  in  the  previous  chapter  is  replaced  by  a  number 
of  electrically  operated  switches,  called  contactors,  which  are 
placed  under  each  motor  car,  and  there  is  also  a  separate 
electrically  operated  reversing  switch  called  the  reverser. 
These  contactors  and  the  reverser  fulfill  the  same  functions 
as  the  controllers  on  a  single  car,  making  the  same  combina- 
tion of  the  motors  and  starting  resistances.  Instead,  how- 
ever, of  being  directly  operated  by  the  motorman  they  are 
operated  through  a  small  controller,  called  the  master  con- 
troller, to  which  all  the  conductors  and  reversers  on  the  train 
are  attached  by  means  of  a  control  circuit  cable.  This  cable 
runs  the  entire  length  of  the  train  and  is  connected  from  car 
to  car  by  means  of  suitable  couplers,  and  when  trail  cars  are 
placed  between  motor  cars  they  are  also  provided  with  cables. 
The  platforms  of  each  motor  car  and,  if  desired,  those  of 
each  trail  car  are  equipped  with  a  master  controller  so  that 
the  train  may  be  operated  from  the  platform  of  whichevei 
car  happens  to  be  in  front. 

The  master  controller,  type  C  6,  shown  in  Fig.  85,  al- 
though smaller  than  the  ordinary  car  controller,  is  similar  in 
appearance,  and  method  of  operation.  It  has  separate  power 
and  reverse  handles  and  it  contains  a  magnetic  blow-out 
similar  to  that  of  the  ordinary  controller.  All  the  current 


135 


for  the  operation  of  the  conductors  is  taken  from  the  line 
and  passes  directly  through  whichever  master  controller  hap- 


pens to  be  in  use,  and  the  handle  of  the  master  controller  is 
generally  arranged  so  that  if  the  motorman  removes  his 
hand  from  it  the  control  circuit  will  be  broken  and  the  con- 


136 

tactors  opened,  thus  shutting  off  all  current  from  the  motors. 
The  reverse  handle  can  only  be  removed  when  it  is  in  the 
off  position  and  the  power  handle  is  mechanically  locked 
when  the  reverse  handle  is  removed. 

The  contactors  each  consist  of  a  movable  arm  with  a  re- 
movable copper  contact  at  one  end,  making  contact  with  a 
similar  fixed  contact  piece,  and  a  coil  which  actuates  the  arm 
when  supplied  with  current  from  the  master  controller.  The 
contactor  is  closed  only  when  the  current  of  the  control  cir- 
cuit passes  through  its  coil  and  gravity,  assisted  by  the 
spring  action  of  the  contact  piece,  causes  the  arm  to  drop  and 
the  circuit  to  open  when  the  control  circuit  is  broken.  The 
contactor  also  has  a  powerful  magnetic  blow-out.  The  re- 
verser  is  somewhat  similar  to  the  ordinary  reversing  switch 
with  the  addition  of  electro-magnets  for  turning  it  either  to 
the  forward  or  reverse  positions.  Its  operating  coils  are  sim- 
ilar to  those  of  the  contactors.  A  cut-out  switch  is  also  pro- 
vided by  means  of  which  all  of  the  control  operating  circuits 
on  any  car  may  be  cut  out. 

It  will  be  evident  from  the  foregoing  explanation  that 
there  are  two  principal  circuits  on  a  car  equipped  with  the 
type  M  control :  First,  the  control  circuit  which  passes  from 
the  line  to  the  contact  shoe  on  the  car,  thence  to  the  master 
controller,  thence  through  the  various  operating  coils  of  the 
contactors  and  reversers  and  thence  to  the  ground  return ; 
Second,  the  motor  circuit,  which  from  the  contact  shoe  passes 
through  the  various  contactors,  thence  to  the  motor  fields  and 
armatures  and  thence  to  the  ground  return.  All  of  the  con- 
tactors under  each  car  taken  together  constitute  a  series 
parallel  controller  and  the  different  combinations  of  the  con- 
tactors is  indicated  by  the  position  of  the  master  controller 
handle.  The  diagram,  Fig.  86,  shows  the  complete  connec- 
tions of  the  C-6  controller  and  its  auxiliary  apparatus  for 
a  two-motor  equipment.  The  running  points  on  this  con- 


C-6  Controller 

I9ever*e        Forwar< 


Cootn 
Coupler  SocKets 


Third   R«il    Shoe 


C-6    Controller 


Reverse 
'Cylinder 


Auxiliary    f*   »  8to£'-l'out 
Contacts  [^  *g~i       Coil 

Runn.no    PointS---K) s' 

Resist  Shoe    Points;.  9  8-76 '--A  321 


From  this   Cable 
Oo  8    Wire   connects  to   O 
no  O  •  to   8 

at  Connection  Board   no  2 


Control 

Coupler  Sockets 


Operating  Coi 


Copyright,  1903,  by  General  Electric  Co. 


137 

troller  are  5  and  10,  5  being  the  series  connection  of  the 
motors  and  10  the  parallel  connection.  The  intermediate 
points  are  resistance  points.  As  this  system  of  control  is 
made  up  of  separate  electrically  operated  switches  these 
may  be  located  in  any  available  position  and  are  generally 
placed  under  the  car  floor. 

The  Westinghouse  multiple  train  control  system  employs 
compressed  air  to  operate  the  controlling  apparatus,  electro- 
magnetic valves  for  controlling  the  admission  of  air  to  the 
various  cylinders  and  a  low  voltage  control  circuit  for  actu- 
ating the  electro-magnets.  The  essential  parts  of  this  system 
consist  of  a  series  parallel  controller  on  which  is  mounted 
an  operating  head  consisting  of  a  number  of  air  cylinders,  a 
multiple  control  switch  and  two  sets  of  storage  batteries. 

The  controller  and  operating  head  combines  a  series 
parallel  controller  with  an  operating  cylinder,  a  release  cylin- 
der, two  reverse  cylinders,  a  repeating  switch,  a  limit  switch, 
four  magnetic  valves  and  two  safety  switches.  The  operat- 
ing cylinder  carries  two  pawls  on  the  end  of  its  piston  rod 
which  engage  two  ratchet  plates  mounted  on  the  end  of  the 
controller  shaft  and  these  pawls  turn  the  controller  notch 
by  notch.  The  release  cylinder  throws  the  controller  to  the 
"off"  position.  The  reverse  cylinders  are  used  to  throw  the 
reverser  to  "forward"  or  "back"  and  the  magnet  valves  admit 
or  cut  off  the  air  in  the  different  cylinders.  The  repeating 
switch  causes  the  controller  to  advance  notch  by  notch  auto- 
matically as  the  car  is  accelerating  and  the  limit  switch  stops 
the  advance  of  the  controller  when  too  much  current  is  being 
taken  by  the  motors  The  safety  switch  prevents  the  reverse 
switch  from  being  thrown  or  the  circuit  breaker  from  being 
closed  except  when  the  controller  is  at  the  "off"  position. 
All  of  the  pistons  of  the  air  cylinders  move  against  springs 
v/hich  return  them  to  their  normal  positions  when  the  air 
is  cut  off. 


138 

A  multiple  control  switch,  which  is  operated  by  the  motor- 
man,  is  placed  on  each  end  of  each  car  and  a  train  is  con- 
trolled from  the  one  on  the  front  of  the  leading  car.  This 
switch  only  controls  the  low  voltage  battery  circuits  which 
operate  the  magnet  valves.  Two  sets  of  batteries  are  used 
alternately,  one  set  being  charged  on  the  lighting  circuit  of 
the  car  while  the  other  set  is  being  discharged.  The  bat- 
tery circuits  are  connected  from  car  to  car  by  means  of  flexi- 
ble cables  coupled  between  the  cars,  and  the  supply  of  air 
for  the  controller  cylinders  is  taken  from  the  air-brake  cylin- 
ders under  the  cars. 

When  the  multiple  control  switch  handle  is  moved  to  the 
right  to  the  first  notch  the  battery  circuit  is  closed  through  a 
magnet  switch  which  opens  a  valve  admitting  air  to  one  of 
the  cylinders  and  the  piston  in  this  cylinder  is  moved  for- 
ward against  its  spring.  The  function  of  the  spring  is  to 
open  the  circuit  breaker.  On  notch  2  of  the  control  switch 
the  battery  circuit  is  closed  through  the  other  magnets,  one 
of  which  opens  a  valve  to  one  of  the  reverse  cylinders  which 
the  air  pressure  turns  to  the  "forward"  position.  From  the 
reverse  cylinder  the  air  passes  through  a  pipe  to  the  circuit 
breaker  cylinder,  where  it  closes  the  circuit  breaker.  An- 
other magnet  shuts  off  the  air  from  the  release  cylinder  and 
opens  an  exhaust  from  it  to  the  atmosphere.  When  the  con- 
trol switch  handle  is  moved  to  notch  3  the  circuit  is  closed 
through  the  operating  cylinder  magnet,  the  repeating  switch 
and  the  safety  switch.  In  this  position  of  the  control  switch 
air  is  admitted  to  the  operating  cylinder  whose  piston  moves 
forward  and  turns  the  controller  cylinder  one  notch  by 
means  of  the  pawl  and  ratchet  wheel.  When  this  piston 
reaches  the  end  of  its  stroke  an  arm  which  it  carries  opens 
the  repeating  switch.  This  cuts  off  the  supply  of  air  from 
the  operating  cylinder  and  the  spring  moves  its  piston  back 
until  the  arm  closes  the  repeating  switch  and  the  piston 


139 

carrying  the  pawl  again  moves  forward  and  turns  the  con- 
troller to  the  next  notch.  This  operation  is  repeated  sev- 
eral times  until  the  controller  stands  at  the  full  series  posi- 
tion, when  it  is  stopped  through  the  action  of  an  interlock- 
ing switch.  When  the  control  switch  handle  is  moved  to 
notch  4  the  automatic  notching  up  of  the  controller  proceeds 
until  the  full  multiple  position  is  reached.  On  throwing  the 
control  handle  back  to  notch  i  the  air  is  cut  off  from  the 
operating  cylinder  and  admitted  to  the  release  cylinder 
through  the  action  of  their  respective  magnets.  The  release 
cylinder  piston  in  moving  carries  a  rack  with  it  which  turns 
the  controller  to  the  "off"  position  by  means  of  the  pinion 
on  its  shaft.  The  pipe  furnishes  connection  between  the 
brake  cylinder  and  the  release  cylinder  so  that  the  controller 
is  automatically  opened  when  the  brakes  are  applied.  The 
controller,  also,  cannot  be  thrown  on  until  the  brakes  are 
released. 

To  operate  the  train  after  all  connections  are  made  ready 
and  the  air  pump  has  compressed  the  air  in  the  brake  cylinder 
to  the  proper  pressure,  move  the  handle  to  notch  i,  which 
admits  air  to  the  circuit  breaker  cylinders  on  each  car ;  then 
advance  the  handle  to  notch  2  and  let  it  remain  there  a  few 
seconds  and  then  move  it  to  notch  3.  When  at  this  point  the 
controllers  on  all  the  cars  will  advance  step  by  step  to  the 
full  series  position.  By  pressing  a  latch  in  the  handle  and 
moving  it  to'  notch  4  all  the  controllers  will  advance  to  the 
full  multiple  position.  The  speed  at  which  the  controllers 
will  advance  depends  upon  the  limit  switch  which  is  ar- 
ranged to  stop  the  action,  of  the  controller  when  a  fixed 
maximum  of  current  is  taken  by  the  motors. 

The  controllers  may  be  stopped  in  any  position  by  bring- 
ing back  the  handle  to  notch  2,  but  they  should  only  be  al- 
lowed to  stand  at  the  shunt  positions  but  a  short  time.  The 
current  is  cut  off  from  the  motors  entirely  by  bringing  the 


140 

handle  back  to  notch  I.  In  order  to  avoid  delay  in  starting, 
the  handle  may  be  advanced  to  pcint  2  before  the  starting 
signal  is  given,  and  this  allows  the  train  to  be  started  im- 
mediately by  moving  the  handle  to  notch  3.  For  the  general 
inspection  and  remedying  of  troubles  on  this  system  the 
reader  is  referred  to  a  book  of  instructions  published  by  the 
Westinghouse  Air  Brake  Co. 


CHAPTER  V. 

BRAKES  AND  THEIR  CONSTRUCTION. 

The  brake  is  a  most  important  device  for  the  motorman, 
because  its  purpose  is  to  control  the  car  when  the  power  is 
cut  off  and  cause  it  to  slow  up  or  stop  at  any  desired  place. 
The  brake,  when  applied,  consumes  the  energy  stored  in  the 
car  by  the  motors.  This  energy  is  overcome  by  the  friction 
of  the  brake  shoes  on  the  car  wheels.  The  better  a  motor- 
man can  estimate  the  distance  and  the  less  he  has  to  use  up 
the  stored  energy  with  the  brake,  the  more  efficient  are  his 
services,  the  less  is  the  power  wasted.  It  will  be  clear  to 
apply  the  power  up  to  the  last  moment  and  immediately 
afterwards  use  the  brake  is  a  wasteful  performance,  but 
there  are  conditions  where  such  action  cannot  be  avoided, 
for  instance  when  stopping  on  a  grade  or  when  a  motorman 
has  to  make  many  stops  and  his  time  for  a  round  trip  is 
measured  closely  with  respect  to  the  speed  of  the  motor  in 
use. 

But  before  discussing  the  way  to  handle  brakes  let  us  look 
into  the  construction  of  some  of  the  principal  brakes  in  use. 
There  are  at  present  in  use  five  kinds  of  brakes. 

1.  Hand  brakes  in  which  the  power  which  draws  the 
brake  shoes  against  the  wheels  is  supplied  by  the  strength 
of  the  motorman,  either  by  the  winding  of  a  chain  on  a  staff 
or  as  on  a  few  roads  by  a  long  lever. 

2.  Momentum  or  friction  disk  brakes  in  which  the  mo- 
mentum of  the  car  furnishes  power  to  draw  up  the  brake 
shoes  through  the  medium  of  a  friction  disk  or  clutch  placed 
on  one  axle. 


142 

3.  Air  brakes,  in  which  the  power  drawing  up  the  brake 
shoes  is  compressed  air  acting  against  a  piston. 

4.  Electric  brakes,  in  which  the  retarding  force  is  the 
electricity  generated  in  the  motors  which  are  connected  to  act 
as  dynamos,  the  motors  in  this  case  being  used  to  stop  the 
car  as  well  as  to  start  it  and  run  it. 

5.  Track  brakes,  in  which  shoes  carried  at  the  sides  of 
the  truck  are  pressed  against  the  top  of  the  track  rails  with 
sufficient  force  so  that  the  friction  between  the  shoes  and 
rails  stops  the  car. 

While  hand  brakes  are  used  on  all  electric  cars,  all  but 
the  smallest  and  lightest  cars  are  now  generally  equipped 
with  some  kind  of  power  brakes.  Every  truck  has  a  brake 
mechanism  consisting  of  various  arrangements  of  rods, 
beams  and  levers  by  means  of  which  the  force  applied  to 
the  brake  handle  or  the  brake  levers  is  transmitted  to  the 
brake  shoes  so  that  they  may  be  pressed  hard  against  the 
wheels.  Every  make  of  trucks  has  its  own  style  of  brake 
rigging1  and  the  number  of  different  makes  is  too  great  to 
permit  a  detailed  description  of  them  all,  and  as  the  general 
arrangement  of  all  of  them  is  more  or  less  similar,  a  de- 
scription of  two  or  three  different  syles  of  hand  brakes  will 
suffice. 

Figs.  87,  88  and  89  show  three  views  of  the  truck  equipped 
with  hand  brakes.  Fig.  87  is  a  top  view,  Fig.  88  a  front  ele- 
vation and  Fig.  89  a  side  elevation.  The  brake  shoes,  5, 
are  located  close  behind  the  car  wheels  i,  2,  3  and  4,  the  nor- 
mal distance  between  the  brake  shoes  and  wheels  being 
about  one-eighth  of  an  inch.  The  shoes  are  supported  by 
brake  beams,  6,  to  which  are  fastened  the  brake  rods,  7.  The 
other  ends  of  the  brake  rods  are  securely  fastened  to  the 
cross  beams,  8,  which  in  turn  engage  at  9  with  the  equalizer 
bar.  At  the  ends  of  the  equalizer  bar  are  secured  the  hook 
rods,  ii,  into  which  the  brake  chain  is  hooked.  The  chain, 


144 

brake,  staff  and  handle  are  not  shown  in  these  drawings.  A 
heavy  spring,  12,  is  used  to  remove  the  brake  shoe  from 
the  car  wheels  when  the  brake  is  released.  The  action  that 
takes  place  in  braking  the  car  is  as  follows : 

When  the  motorman  turns  the  brake  handle  around  one  or 
more  turns  he  winds  up  the  brake  chain  and  pulls  the  hook 
rod,  II,  forward  and  thereby  moves  the  equalizer  bar,  10, 
which  in  turn  moves  the  cross  beams,  8,  8.  These  cross 
beams  in  moving  towards  each  other  move  rods  7,  and  these 
in  turn  bring  the  brake  beams,  6,  and  shoes,  5,  toward  each 
other  until  the  shoes  rest  firmly  against  the  car  wheels. 
When  the  brake  handle  is  released,  all  the  parts  return  to 
their  former  position.  The  spring,  12,  assists  in  this  latter 
work  and  helps  to  hold  the  brake  shoe  away  from  the 
wheel.  It  will  be  seen  from  this  that  all  four  brake  shoes 
act  at  the  same  time.  It  is  necessary  to  provide  an  adjust- 
ment in  every  brake,  because  the  brake  shoes  wear  and  the 
slack  caused  by  this  wear  must  be  taken  up.  In  the  truck 
just  described  this  adjustment  is  made  where  the  rods,  7, 
connect  to  the  brake  beam  at  points  14  near  the  shoes.  These 
rods  have  threaded  ends  that  screw  into  sleeve  nuts,  15, 
which  are  held  in  pockets  provided  for  them  in  the  brake 
beam.  A  self-locking  device  prevents  these  ends  from  turn- 
ing loose  by  the  jolting  of  the  car.  The  adjustment  is  made 
by  turning  the  head  of  the  nut  with  a  wrench.  The  head 
is  at  the  outer  enclosed  side  of  the  nut,  and  turning  it  to  the 
right,  or  clockwise,  shortens  the  rod  and  brings  the  shoe 
nearer  the  wheel.  The  locking  device  does  not  interfere  with 
turning  the  nut  with  a  wrench,  but  it  prevents  the  nut  from 
turning  due  to  the  jolting  of  the  car.  These  adjustments  are 
placed  near  the  brake  shoes  because  this  location  enables  the 
adjustment  of  each  shoe  separately,  and  consequently  all  the 
shoes  may  be  regulated  for  an  equal  pressure  on  their  wheels. 
Fig.  90  shows  another  brake  mechanism  which  is  used  on 


145 

the  Taylor  single  trucks.  The  brake  mechanism  is  shown 
in  full,  and  the  car  wheels  and  truck  are  indicated  in  dotted 
lines.  At  the  right  of  the  illustration  is  seen  the  projecting 
hook  rod,  which  is  connected  to  lever  2.  This  lever  is  at- 
tached slightly  out  of  center  to  the  break  beam  3,  which 
carries  the  two  front  brake  shoes,  4,  4.  The  equalizer  rod, 
5,  is  attached  to  lever,  2,  by  means  of  a  link,  6.  From  the 
equalizer  the  rods,  7,  7,  extend  to  the  middle  of  the  car  and 
are  connected  by  turn  buckles,  8,  8,  to  the  exact  duplicate  of 
the  mechanism  described  on  the  other  end  of  the  car.  The 
turn  buckles  have  a  right  hand  thread  tapped  into  one  end 
and  a  left  hand  thread  in  the  other,  so  that  turning  them  in 
one  direction  will  unscrew  or  lengthen  both  rods,  7,  7,  and 
the  distance  between  the  equalizer  bars.  Turning  the  turn 
buckles  in  the  opposite  direction  shortens  the  rods,  7,  7,  and 
consequently  the  distance  between  the  equalizer  bars.  When 
these  are  shortened  the  brake  shoes,  4,  4,  are  brought  closer 
together.  This  brake  is  designed  to  secure  an  even  pressure 
upon  all  the  wheels  at  the  same  instant,  even  though  the 
adjustment  on  both  sides  should  not  be  exactly  the  same. 
If  the  man  in  charge  of  the  cars  takes  up  more  slack  on  one 
side  of  the  brake  than  on  the  other,  the  equalizer  will  com- 
pensate for  the  difference,  so  that  each  shoe  bears  against 
each  wheel  with  the  same  pressure.  When  the  brakes  are 
idle  the  shoes  are  held  a  slight  distance  from  the  wheels  by 
an  adjustable  release  spring,  12,  which  can  be  readily  ad- 
justed so  that  all  the  shoes  are  an  equal  distance  from  their 
respective  wheels.  This  distance  is  from  %  to  3-16  of  an 
inch,  and  in  this  position  the  motorman  can  bring  the  shoes 
against  the  wheels  by  a  single  turn  of  the  brake  handle. 
Under  these  conditions  the  speed  of  a  car  can  be  checked 
quickly,  and  the  car  is  under  easy  control.  It  is  hardly  pos- 
sible to  entirely  disable  these  brakes,  as  the  conductor  can 
apply  the  brake  on  the  rear  end  of  the  car  in  case  anything 


.      $ 

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Mr 


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147 


becomes  disabled  on  the  motorman's  end,  and  if  one  of  the 
brake  rods  and  end  chains  give  way,  the  brake  can  be  oper- 
ated on  the  opposite  end. 

The  McGuire  hand  brake  is  shown  in  diagram  in  Fig.  91. 
The  full  truck  is  not  shown,  but  simply  the  wheels  and  one 
side  of  the  brake.  The  brake  chain  is  attached  to  rod,  i, 
and  when  this  rod  is  drawn  by  the  brake  chain  attached  to 
the  brake  staff,  the  curved  lever,  2,  to  which  it  is  attached,  is 


pulled  over  toward  the  left.  This  lever  is  pivoted  on  the 
brake  beam,  3,  and  has  its  other  end  attached  to  rod,  4,  which 
runs  across  to  the  other  brake  beam,  and  the  rocking  lever,  5. 
It  will  be  seen  that  when  the  rocking  lever,  2,  is  pulled  from 
right  to  left  the  brake  beams  carrying  the  brake  shoes  are 
pulled  together,  and  the  shoes  drawn  against  the  wheel.  To 
adjust  the  brake  shoes  and  bring  them  nearer  the  wheels  a 
nut,  6,  is  provided  on  the  end  of  the  rod,  4.  The  arrange- 
ment of  the  brake  levers  is  the  same  on  the  opposite  side  of 
the  truck,  except  that  the  lever,  2,  is  on  the  opposite  end. 


148 


The  rods  on  the  two  sides  should  be  adjusted  so  there  will 
be  an  even  pressure  on  both  pair  of  brake  shoes 

Fig.  92  shows  the  elastic  brake  shoe  hanger  of  the  Mc- 
Guire  Manufacturing  Company.  The  spring  G  serves  to 
automatically  take  up  the  wear  on  the  pivot  H,  and  also 
acts  as  a  reactive  spring  to  throw  the  shoe  away  from  the 
wheels  when  the  brake  is  released.  The  force  with  which 
these  springs  G  act  on  the  brakes  can  be  regulated  by  the 


ft*  to/ire  Mfq  Co 


PIG.  92. 


nuts  C,  so  that  the  proper  clearance  between  the  shoes  and 
the  wheels  can  always  be  maintained.  For  instance,  if  the 
shoes  on  one  side  of  the  car  do  not  stand  the  same  distance 
from  the  wheels  as  on  the  other  side  when  the  brake  is  re- 
leased, the  nut  C  should  be  slacked  off  on  the  hanger  whose 
shoe  is  farthest  from  the  wheel,  and  tightened  on  the  hanger 
whose  shoe  is  nearest  to  the  wheel.  Many  of  the  older 
McGuire  trucks  have  plain  standard  release  springs  in  place 
of  the  elastic  hanger. 

In  the  case  of  double  truck  cars,  arrangements  must  be 
made  to  apply  the  brakes  on  both  trucks,  so  that  each  will 
be  operated  by  the  motion  of  one  brake  handle.  This  is  ac- 


149 

complished  in  various  ways,  generally  by  having  either  a 
fixed  or  floating  lever  in  the  center  of  the  car  between  the 
trucks,  to  which  the  brake  rods  from  each  truck  are  con- 
nected. The  central  lever  is  then  connected  to  the  brake 
staff  by  means  of  a  brake  chain  and  rod,  and  by  moving  this 
rod  and  the  central  lever  to  which  it  is  attached,  the  brakes 


on  both  trucks  are  operated  simultaneously.  The  arrange- 
ment of  the  levers  of  the  Sterling  brake  for  double  truck 
cars,  which  is  standard  on  the  cars  of  the  Metropolitan 
Street  Railway,  NewT  York  City,  is  shown  in  Fig.  93,  and 
the  following  dimensions  show  the  proportion  of  the  dif- 
ferent levers.  The  length  of  the  floating  lever,  1,  is  48  in.,  and 
the  distance,  d,  between  the  pins  for  the  arch  bar  rods  is  9  in. 
The  length,  b,  of  the  truck  lever  is  13  in.  With  these 
dimensions  of  levers  a  pull  of  65  Ib.  at  the  brake  handle, 
which  is  15  in.  in  length,  gives  a  total  braking  pressure  o|" 


150 


29,000  lb.,  which  is  more  than  the  weight  of  an  empty  car. 
The  proportion  of  the  levers  recommended  by  the  makers 
of  these  brakes  is  such  as  to  make  (1-f-d)  X  (b-i-c)  X(hX 
85)  equal  to  the  total  weight  of  the  unloaded  car.  The 
chain  is  not  coiled  around  the  brake  staff  on  these  brakes, 
but  there  are  two  chains  running  in  a  double  sprocket  wheel 
which  makes  the  operation  of  the  brake  very  smooth  and 
permits  the  motorman  to  feel  even  a  slight  touch  of  the 
brake  shoe  against  the  wheel.  If  the  working  chain  breaks, 


FIG.  94. 


the  safety  chain  comes  into  operation,  thus  preventing  the 
disability  of  the  brakes  from  this  cause. 

The  standard  equalizer  brake  rigging  for  double  truck 
cars  used  by  the  Brill  Co.  is  shown  in  Fig.  94.  The  two 
central  equalizer  levers  are  connected  at  their  fulcrums  by 
a  short  rod,  one  end  of  each  lever  is  connected  by  a  rod  and 
chain  to  the  brake  staff,  and  the  other  end  of  each  lever  is 
connected  by  another  rod  to  the  brake  rigging.  The  object 
of  these  brake  mechanisms  for  double  trucks  is  to  provide  a 
means  for  bringing  an  approximately  equal  pressure  on  all 
of  the  car  wheels  which  is  necessary  in  order  to  secure  the 
maximum  braking  effect,  and  also  to  prevent  one  set  of 


151 


wheels  being  locked  more  firmly  than  the  others,  which 
would  cause  them  to  slide  along  the  track  without  revolv- 
ing, and  produce  flat  spots  on  the  wheels. 

The  Price  momentum  brake  has  a  friction  clutch  on  one 
axle,  from  which  power  is  derived  to  draw  up  the  brake 
chain  which  operates  the  ordinary  brake  rigging.  In  other 
words,  the  friction  clutch  supplies  the  power  which  is  fur- 
nished by  the  muscles  of  the  motorman  when  the  common 
hand  brake  is  used.  With  the  Price  brake  the  motorman 
simply  pulls  a  lever,  which  forces  the  friction  clutch  to  act 


and  draw  up  the  brakes.  The  plan  of  a  truck  equipped  with 
the  Price  brake  is  shown  in  Fig.  95.  The  car  wheel,  a,  has 
a  disc  wheel,  b,  which  may  be  fastened  to  it,  or  as  ordinarily 
used,  is  cast  on  the  wheel.  Against  this  is  a  corresponding 
loose  disc,  e,  located  upon  the  axle.  This  loose  disc  is  pref- 
erably made  in  two  parts  so  that  it  can  be  easily  removed, 
and  the  halves  are  bolted  together  around  the  axle.  It  is 
supported  on  brass  bearings  and  is  provided  with  an  ex- 
tended sleeve  to  which  is  attached  one  end  of  the  chain,  the 
opposite  end  being  secured  to  the  center  lever  of  a  double 
truck  car,  or  to  one  of  the  brake  levers  when  a  single  truck 


152 

is  used.  In  the  early  Price  brakes  the  loose  disc  is  pressed 
against  the  car  wheel  disc  by  a  system  of  levers  controlled 
by  the  motorman,  and  this  causes  the  disc,  e,  to  attempt  to 
revolve  with  the  car  wheel.  This  movement  of  the  disc,  e, 
winds  up  the  brake  chain  attached  to  it,  and  applies  the 
brake.  In  the  modern  Price  brakes  improvemnts  have  been 
made  in  the  method  of  applying  the  power.  A  hydraulic 
pressure  pump  has  been  added  in  combination  with  a  hydrau- 
lic clutch  for  operating  the  brake.  The  pressure  pump  is 
located  on  the  floor  of  the  car  platform,  and  is  operated  by 
means  of  a  vertical  staff,  to  the  upper  end  of  which  a  ratchet 
wheel  is  attached.  The  movement  of  this  handle  drives  the 
plunger  into  the  barrel  of  the  pump  and  makes  it  possible 
to  put  the  desired  pressure  upon  the  liquid  which  it  contains. 
A  pipe  connects  this  pump  with  the  cylinders  of  a  hydraulic 
clutch  that  is  located  on  the  axle  and  operates  the  disc.  In 
order  to  make  a  gradual  application  of  the  friction  disc  to 
the  wheel  an  air  pump  is  provided  in  the  connections,  which 
serves  as  a  cushion  and  permits  the  motorman  to  apply  the 
brakes  as  rapidly  or  as  slowly  as  required  This  brake  has 
an  operating  lever,  which  is  located  close  to  the  dash  between 
the  hand  brake  staff  and  the  motor  controller.  To  apply  the 
brake,  pull  the  lever  slowly  for  an  easy  stop  and  quickly  for 
an  emergency  stop,  and  ease  off  the  pull  on  the  lever  slightly 
just  before  the  car  comes  to  a  stop,  same  as  is  done  with  the 
hand  brake. 

When  going  up  a  grade  do  not  ease  off  the  pull  entirely, 
but  hold  the  brake  on  till  ready  to  start  the  car  again.  If 
the  brake  is  released  on  a  grade  the  car  will  run  backwards, 
but  can  be  brought  to  a  stop  by  applying  the  brake,  same  as 
when  the  car  is  running  down  the  grade. 

The  lever  is  provided  with  a  ratchet  and  pawl,  but  these 
should  not  be  used  until  after  the  car  comes  to  a  stop  and 
when  it  is  desired  to  hold  the  brake  on. 


153 


Before  leaving  the  car  platform  always  set  the  hand  brake. 

Air  brakes  are  now  very  generally  used  on  heavy  electric 
cars,  and  are  principally  of  two  kinds,  known  as  the  straight 
air  and  the  automatic  air  brake.  The  "straight"  air  brake 
is  the  more  common  on  electric  cars,  however,  and  is  also 


FIGS.  %  AND  97. 

more  simple,  as  we  will  describe  the  "straight"  air  brake 
first,  taking  as  an  example  the  Standard  Air  Brake  Com- 
pany's apparatus.  Fig.  97  shows  a  side  view  of  a  car  piped 
for  Standard  air  brakes  and  Fig.  96  the  plan  of  the  piping 
as  it  would  look  from  above.  The  air  is  pumped  by  the  elec- 
tric compressor  under  the  seat  into  the  reservoir.  The  com- 
pressor is  simply  an  air  pump  driven  by  an  electric  motor. 
In  some  cases  the  pump  is  constantly  driven  from  the  car 


154 

axle  instead  of  a  motor.  The  air  pump  is  connected  with 
the  reservoir  where  the  air  is  kept  constantly  stored  under  a 
pressure  of  from  30  to  40  pounds  per  square  inch.  Auto- 
matic regulators  shut  off  the  electric  pump  motor  when  the 
pressure  reaches  40  pounds,  or  if  the  compressor  is  driven 
from  the  axle  the  pump  is  made  to  exhaust  into  the  open  air 
when  the  pressure  rises  to  that  amount.  From  the  reservoir, 
pipes  run  to  the  motorman's  valves  on  each  platform  and 
pipes  also  connect  the  motorman's  valves  with  the  brake 
cylinder.  The  brake  cylinder  has  a  piston  which  is  con- 
nected to  the  brake  shoe  rig  of  the  truck.  To  apply  the 
brakes  the  motorman's  valve  is  turned  so  as  to  let  the  air 
pressure  from  the  reservoir  into  the  brake  cylinder  which 
pushes  out  the  piston  and  applies  the  brakes.  To  release 
brakes  the  valve  is  turned  so  as  to  let  the  air  escape  from 
the  brake  pipe  and  close  the  way  from  the  reservoir  to  the 
brake  pipe.  If  a  trailer  is  used  its  brake  pipe  is  connected 
to  that  of  the  motor  car,  so  that  the  pressure  let  into  the 
motor  car  brake  cylinder  also  goes  to  the  trailer  brake  cylin- 
der. 

The  handle  of  the  motorman's  valve  should  always  be  on 
release  position,  that  is  to  the  extreme  right,  when  the  car 
is  running.  Between  the  position  of  "application"  and  "re- 
lease" there  is  the  position  of  lap.  When  making  a  service 
stop  the  handle  should  be  moved  to  the  left  until  it  is 
slightly  to  the  left  of  lap  and  immediately  back  to  the  lap 
position.  This  will  admit  some  air  pressure  to  the  brake 
cylinder.  The  suddenness  of  the  stop  depends  on  the  dis- 
tance the  handle  is  moved  past  "lap"  and  the  length  of  time 
it  is  left  there.  To  make  an  emergency  stop  immediately 
throw  handle  over  as  far  to  the  left  as  possible  and  keep  it 
there.  This  lets  the  full  pressure  into  the  brake  cylinder. 
On  slippery  track  some  judgment  must  be  used,  however, 
in  making  an  emergency  stop  not  to  slide  the  wheels.  The 


155 

air  brake,  and  especially  the  compressor,  needs  regular  at- 
tention and  oiling. 

The  general  plan  of  the  Christensen  air  brakes,  which 
are  very  extensively  used  on  electric  cars,  is  shown  in  Fig. 
98.  The  compressor  consists  of  a  self-contained  enclosed  air 
pump  which  is  either  directly  attached  to  the  car  axle,  being 
operated  by  an  eccentric,  or  is  driven  by  a  separate  electric 
motor.  The  suction  and  discharge  valves  are  so  arranged 
that  when  the  maximum  presure  is  reached  the  compressor 
stops  working  automatically,  and  does  not  commence  com- 
pressing again  until  the  pressure  is  lowered.  In  Fig.  99 
is  shown  the  plan  of  equipment  for  a  motor  car  and  trailer. 
In  the  motor  driven  air  compressor  equipments,  the  current 
for  the  motor  is  taken  directly  from  the  trolley  and  the 
action  of  the  motor  is  governed  by  an  automatic  switch  con- 
troller which  operates  by  the  variation  in  pressure  due  to 
the  working  of  the  compressor  and  the  consumption  of  air 
by  the  brakes.  Fig.  99  shows  the  connections  for  a  motor  car 
and  trailer. 

The  engineer's  valve  is  the  part  of  this  brake  mechanism 
which  most  directly  concerns  the  motorman,  and  he  should 
become  familiar  with  its  operation  in  the  various  positions 
shown  in  Fig.  100.  The  position  for  releasing  is  the  position 
in  which  the  handle  should  stand  while  the  car  is  running. 
In  this  position  there  is  direct  communication  from  brake 
cylinder  to  atmosphere,  consequently  the  shoes  are  kept 
away  from  the  wheels  by  the  heel  springs.  Don't  run  the 
car  with  the  valve  handle  in  lap  position.  It  should  be  at 
slow  release,  or  between  that  and  quick  release.  In  lap  or 
center  position  all  the  ports  are  closed,  and  it  will  be  ob- 
served that  this  'is  the  only  position  in  which  the  handle  can 
be  removed  from  the  valve  when  changing  from  one  end 
of  the  car  to  the  other.  If  this  change  happens  to  be  on  a 
grade,  the  brakes  are  simply  set,  the  valves  put  in  lap  posi- 


157 


tion,,  and  the  handle  removed,  then  the  brake  is  released  from 
the  other  end.  At  the  emergency  position  a  free  passage  is 
open  for  the  air  to  enter  the  brake  cylinders,  applying  the 
brake  instantly  with  full  force,  and  this  should  only  be  used 


in  case  of  necessity.    The  general  instructions  for  the  opera- 
tion of  the  Christensen  straight  air  brake  are  as  follows  : 

1.  To  start  the  compressor  close  the  canopy  switch.    This 
will  automatically  close  the  governor,  so  that  current  will 
pass  from  trolley  to  ground  through  the  motor,  thus  drivinjr 
the  compressor. 

2.  Should  the  compressor  refuse  to  work  under  this  con- 


158 

dition,  the  fuse  may  be  blown.  If  so,  do  not  put  in  a  heavier 
fuse  than  specified  ior  the  size  of  the  compressor.  If  the 
fuse  is  in  order,  you  should  try  to  locate  the  trouble  if  you 
can  readily  do  so ;  if  not,  you  should  report  the  matter  to  the 
proper  person. 

3.  All  the  stop-cocks  on  the  train  pipe,  except  on  the 
front  and  rear  ends  of  the  train,  should  be  open.     When 
open,  the  handle  stands  crosswise  to  the  pipe  and  when 
closed  it  stands  parallel  with  it. 

4.  To  cut  out  a  standard  governor  close  the  ^4-inch  stop- 
cock so  that  the  T  handle  stands  crossways  with  the  pipe ; 
then  move  the  governor  plunger  so  as  to  make  contact  and 
thus  close  the  circuit.    The  compressor  can  now  be  started 
and  stopped  by  the  hand  switch  in  the  canopy,  but  you 
should  not  forget  to  start  and  stop  the  compressor  to  keep 
the  pressures  within  the  desired  limits  of  70  pounds  mini- 
mum and  80  to  90  pounds  maximum. 

Lap  Position. — The  engineer's  valve  is  made  with  a  de- 
tachable handle,  which  is  only  removable  in  what  is  known 
as  lap  position,  in  which  position  the  valve  is  neutral  in  the 
same  manner  as  the  main  controller  is  by  removing  the  re- 
verse handle. 

Service  application  of  the  brakes  is  effected  by  moving 
the  handle  of  the  engineer's  valve  to  the  first  notch  on  the 
right.  As  soon  as  a  sufficiently  hard  pressure  is  brought 
against  the  wheels,  the  handle  may  be  moved  back  into  lap 
position,  whereby  the  brakes  remain  set  at  that  pressure. 
If  it  is  desired  to  set  the  brakes  a  little  harder,  repeat  the 
operation.  By  moving  back  to  lap  without  releasing,  the 
handle  may  be  removed  and  the  brake  released  from  the 
other  end  of  the  car ;  this  feature  is  very  valuable,  especially 
where  the  terminus  is  on  a  grade. 

Slow  Release  of  the  Brakes. — By  moving  the  handle  from 
lap  position  to  the  first  notch  on  the  left  a  slow  release  of  the 


159 

brakes  is  effected,  which  release  may  be  checked  in  the 
same  way  by  moving  the. handle  back  to  lap  position,  the 
same  as  in.  service  application  of  the  brakes. 

Emergency  Application. — This  is  effected  by  moving  the 
handle  from  lap  as  far  as  it  will  go  to  the 'right,  in  which 
position  a  large  passage  is  afforded  to  allow  compressed  air 
to  travel  from  the  main  reservoir  to  the  brake  cylinder  and 
the  application  of  the  brakes  is  practically  instantaneous.  The 
emergency  application  should  not  be  made  except  when 
absolutely  necessary. 

Quick  Release. — By  moving  the  handle  from  lap  position 
to  the  left  as  far  as  it  will  go,  a  quick  release  is  effected  in 
the  same  manner  as  a  quick  application,  by  establishing  a 
large  opening  from  the  brake  cylinder  to  the  atmosphere, 
whereby  the  pressure  escapes  quickly  from  the  brake  cylin- 
der, thereby  letting  off  the  brakes  in  a  very  short  space  of 
time. 

Running  Position. — When  the  brakes  are  not  being  ap- 
plied or  released,  the  handle  of  the  engineer's  valve  should 
always  be  on  the  first  notch  to  the  left,  or  that  of  slow 
release. 

Brake  Leverage. — The  leverage  and  total  pressure  on  the 
brake  cylinder  is  so  proportioned  that  under  ordinary  cir- 
cumstances, with  a  dry  rail,  the  wheels  cannot  skid.  If  the 
rail  is  in  bad  condition  for  stopping,  the  leverage  and  pres- 
sure being  the  same  as  under  normal  conditions,  would  prob- 
ably skid  the  wheels  if  the  brake  cylinder  be  charged  with 
the  full  pressure. 

In  such  instances  care  should  be  taken  not  to  slide  the 
wheels,  by  not  introducing  too  much  pressure  to  the  brake 
cylinder.  If  the  wheels  slide,  which  can  be  instantly  felt, 
the  handle  is  moved  over  to  slow  release,  letting  out  air  until 
the  wheels  again  revolve,  then  back  to  lap,  and  release  again 
just  before  the  car  comes  to  a  dead  stop,  to  prevent  the  dis- 


160 

agreeable  jar  which  follows  if  a  car  comes  to  a  dead  stop 
with  the  brakes  applied. 

The  Westinghouse  air  brake  is  the  one  in  general  use  on 
steam  roads.  With  it  the  pressure  is  kept  constantly  on 
the  uain  pipe  from  one  end  of  a  train  to  the  other.  A  re- 
duction of  this  pressure  causes  an  application  of  the  brakes 
so  that  letting  air  out  of  the  train  pipe,  either  by  the  motor- 
man's  handle  or  by  the  breaking  of  a  hose,  will  set  the 
brakes.  To  explain  properly  the  action  and  mechanism  of 
these  brakes  would  take  more  space  than  is  allowable  in  this 
book,  and  we  would  refer  any  motorman  handling  these 
brakes  to  the  instruction  books  issued  by  the  Westinghouse 
Air  Brake  Company. 

The  General  Electric  Cpmpany's  electric  brake,  which  is 
in  use  on  a  number  of  cars,  has  as  its  fundamental  principle 
the  utilizing  of  the  live  energy  stored  in  the  moving  car  to 
generate  an  elctric  current  in  the  motors  independent  from 
the  power-house  current,  and  the  use  of  this  current  to 
bring  the  car  to  a  standstill.  It  is  produced  in  the  motors 
which  are  connected  to  act  as  dynamos.  It  stops  the  car 
partly  by  its  retarding  effect  on  the  motors  themselves  and 
partly  by  a  magnetic  disc  mounted  on  each  axle.  The  con- 
trollers used  with  the  General  Electric  Company's  electric 
brake  are  of  the  B  type.  The  action  is  as  follows :  Suppose 
a  car  provided  with  an  electric  brake  is  to  be  brought  to  a 
stop.  The  motorman  first  brings  his  controller  to  the  "off" 
position  and  thereby  disconnects  the  car  from  the  line  and 
power  house ;  then  by  moving  the  handle  around  to  the  left 
of  "off"  position  to  the  special  brake  notches,  the  armature 
connections  are  reversed  and  the  motors  are  connected  to 
form  a  closed  circuit  through  a  resistance  and  the  brake 
disc  magnets,  as  shown  in  Fig.  101.  The  motors  running 
with  the  circuit  closed  in  this  way  act  as  dynamos  and  gen- 
erate current.  This  current  tends  to  stop  the  motors  and 


161 


also  to  cause  the  magnetic  clutch  on  the  axle  to  act  and  aid 
in  stopping-  the  car. 

To  operate  an  electric  brake  requires  a  little  practice  on 
the  part  of  the  motorman,  but  when  the  principle  is  clear  it 
is  an  easy  matter.  It  should  first  be  understood  that  the 
amount  of  current  generated  in  the  motors,  and  conse- 
quently the  braking  effect,  depends  on  the  speed  at  which 
the  motors  are  running,  and  that  if  the  brakes  are  to  take 


Ktqutottd 
'Ora/it  Cent  foliar 


for  SJmfi/icitu  rtt*  Llmtt  SHitch  As  Nof  Show/*  -= 


hold  evenly  from  the  beginning  to  end  of  a  stop  the  resist- 
ance which  is  in  the  brake  circuit  must  be  steadily  cut  out. 
For  example,  when  it  is  desired  to  stop  when  running  at  full 
speed,  the  controller  handle  is  moved  to  the  first  brake 
point.  The  motors  start  generating  current  to  retard  the 
car,  but  as  the  car  slows  down  a  little  this  current  begins  to 
die  out,  and  the  handle  should  be  promptly  moved  onto  the 
next  point  to  cut  out  some  more  of  the  resistance  from  the 
brake  circuit  and  allow  more  current  to  flow,  and  so  on  un- 
til the  car  is  stopped.  The  motorman  should  promptly  ad- 


162 

vance  the  handle  from  one  point  to  the  next  of  the  brake 
controller  as  fast  as  he  feels  the  current  failing  on  a  point. 
The  quickness  of  the  stop  will  depend  on  the  rapidity  with 
which  the  handle  is  moved  from  point  to  point,  and  in  emer- 
gencies it  may  be  found  necessary  to  move  two  or  more 
points  at  a  time.  There  is  never  need  to  reverse  on  a  car 
having  an  electric  brake,  as  the  brake  will  stop  as  quick  or 
quicker  than  reversing  and  is  not  so  hard  on  the  machinery. 
On  grades  it  is  necessary  to  use  the  hand  brake  to  hold  the 
car  while  stopping,  for  the  electric  brake  lets  go  as  soon  as 
the  car  stops. 

The  electric  brake  on  the  Walker  type  S  controller  is  de- 
scribed in  the  foregoing  chapter  on  controllers. 

The  Murrey  anti-friction  brake  has  a  cast  iron  collar 
keyed  to  the  car  axle  next  to  the  wheel  and  also  a  brass 
sleeve.  Around  the  sleeve  is  a  drum  which  is  free  to  rotate 
and  around  which  the  brake  chain  winds.  A  portion  of  the 
sleeve  is  threaded,  and  the  nut  covering  this  part,  which  is 
separated  from  the  drum  by  ball  bearings,  has  a  lever  pro- 
jection. Two  levers  connect  to  the  car  platform,  and  by 
forcing  them  forward  the  drum  is  set  against  the  revolving 
collar  and  the  friction  causes  the  drum  to  revolve,  winding 
the  chain  and  setting  the  brake.  The  ball  bearings  enable 
any  pressure  to  be  maintained  and  render  it  impossible  for 
the  brake  to  set. 

The  Magann  air  brake  system  uses  compressed  air  which 
is  stord  in  tanks,  but  is  not  compressed  upon  the  car  as  in 
the  air  brakes  previously  described.  At  the  car  barn  or 
other  central  point  a  storage  tank  is  provided  containing 
compressed  air  at  about  30  pounds  pressure  per  square  inch, 
and  the  tanks  on  the  car  are  filled  from  this  storage  tank  in 
a  few  moments.  A  sufficient  tank  capacity  is  provided  to  be 
sufficient  for  from  300  to  500  stops,  or  several  round  trips 
over  an  ordinary  city  route.  The  initial  pressure  in  the 


163 


main  reservoir  on  the  car  is  usually  300  pounds  per  square 
inch ;  by  a  reducing  valve  this  is  lowered  to  50  pounds  or 
less,  according  to  the  speed  and  weight  of  the  cars,  at  which 
pressure  the  air  enters  the  auxiliary  reservoirs  on  the  cars. 
From  the  auxiliary  reservoir  to  the  brake  cylinder  the  air  is 
controlled  by  the  engineer's  valve.  The  brake  cylinder  is 
provided  with  two  pistons  adapted  to  be  pressed  towards 
each  other  through  the  agency  of  a  spring,  or  other  similar 
means ;  means  are  provided  by  the  motorman's  valve  for 
connecting  the  air  supply  or  reservoir  to  the  space  between 
the  pistons  whereby  the  pistons  may  be  separated  against  the 
tension  of  the  spring  to  apply  the  brake  when  it  is  desired. 

To  release  the  brake  a  controlling  valve  is  operated  to  cut 
off  the  space  between  the  pistons  from  the  air  supply  reser- 
voir, and  to  connect  it  with  the  air  space  of  the  cylinder  be- 
hind the  pistons  whereby  the  pressure  on  the  opposite  side  of 
the  piston  is  equalized  and  the  springs  permitted  to  return 
to  their  normal  positions. 

By  this  arrangment  of  exhaust,  fresh  air  is  always  sup- 
plied behind  the  pistons,  thereby  overcoming  the  danger  of 
accumulating  dust  in  the  cylinder,  and  by  connecting  the 
compressed  air  between  the  pistons  with  the  cylinder  behind 
the  pistons  when  releasing  the  brakes,  the  pressure  on  both 
sides  of  the  piston  is  rapidly  equalized  and  the  springs  at 
once  force  the  pistons  together. 

The  Magann  storage  air  brakes  are  operated  in  practi- 
cally the  same  way  as  other  straight  air  brakes.  To  start  the 
car,  turn  the  handle  to  the  right  until  the  shoes  are  felt  grip- 
ping the  wheels  and  then  place  the  valve  on  lap  position.  The 
lap  position  is  the  one  at  which  the  handle  can  be  put  on  and 
taken  off  from  the  valve.  If  the  car  does  not  stop  as  quickly 
as  desired,  turn  the  handle  to  the  right  again  until  the 
shoes  grip  the  wheels  more  firmly.  The  operation  can  be 
repeated  again  if  necessary.  Turning  the  handle  to  the  left 


164 


allows  the  air  in  the  brake  cylinders  to  exhaust  and  throws 
off  the  brakes.  Just  before  coming  to  a  dead  stop  the  handle 
should  be  turned  to  the  left  so  as  to  allow  most  of  the  air  in 
the  brake  cylinder  to  exhaust. 

The  Westinghouse  magnetic  brake  consists  of  a  combina- 
tion of  a  track  brake  with  the  ordinary  wheel  brake.  The 
track  brake  shoe  is  placed  between  the  two  pairs  of  wheels 
and  instead  of  being  forced  upon  the  wheels  through  an  ef- 


fort  of  the  car,  is  drawn  to  the  rails  by  an  electro-magnet 
suspended  from  the  car.  This  not  only  adds  the  track 
brake  friction  to  the  wheel  friction  for  stopping  the  car,  but 
there  is  an  increase  in  the  wheel  pressure  on  the  rails  due 
to  magnetic  action.  The  construction  of  this  brake  is  shown 
in  Fig.  102,  in  which  the  parts  of  the  truck  are  in  dotted 
lines  so  as  to  more  readily  distinguish  the  brake  apparatus. 
The  electro-magnet,  a,  dividing  the  track  brake  shoe,  b,  into 
two  parts,  is  secured  by  pins  to  the  two  push  rods,  c,  and  sus- 
pended at  the  proper  distance  above  the  rails  by  the  adjust- 
able springs,  h.  The  push  rods  are  secured  by  pins  to  the 


165 

lower  ends  of  the  brake  lever,  d,  which  are  connected  at  their 
upper  ends  by  the  adjustable  rod,  g,  and  at  an  intermediate 
point  are  pivoted  to  the  brake  shoe  holders  and  the  hanger 
links,  f,  suspended  from  the  truck  frame.  The  push  rods,  c, 
are  telescopic,  as  shown  in  the  sectional  view  of  the  one  at 
the  left,  so  that  a  movement  of  the  track  shoe  toward  the 
right  relative  to  the  truck  frame  causes  the  wheel  brake 
shoe  at  the  right  to  be  applied  to  the  wheel  and  the  connec- 
tion, g,  to  be  moved  to  the  left,  thereby  applying  the  wheel 
brake  shoe  at  the  left,  the  stop,  i,  preventing  the  lower  end 
of  the  brake  lever  at  the  left  from  following  the  track  brake 
shoe.  A  relative  movement  of  the  track  brake  shoe  to  the 
left  is  obviously  accompanied  by  application  of  the  wheel 
brake  shoes  through  corresponding  movement  of  the  parts 
in  the  reverse  order. 

The  brake-controlling  device  may  be  incorporated  in  the 
running  controller  or  may  be  a  separate  device,  placed  by  its 
side  and  operatively  interlocked  with  it,  so  that  neither  can, 
through  carelessness,  be  caused  to  interfere  with  the  opera- 
tion of  the  other.  These  controllers,  type  B,  were  described 
in  the  previous  chapter.  In  the  operation  of  the  apparatus, 
the  current  is  supplied  by  the  motors,  running  in  multiple  as 
generators,  and  is  divided  between  the  electro-magnets  and 
the  diverter,  in  such  ratio  as  to  cause  the  track  brake  shoes 
to  be  drawn  upon  the  rails  with  a  force  proportionate  to  the 
braking  requirements.  The  frictional  resistance  of  the  rails 
to  the  motion  of  the  track  shoes  causes  the  wheel  brakes  to 
be  applied  with  corresponding  force.  Thus,  to  the  ordinary 
retardation  of  the  wheel  brakes  is  added  that  of  the  track 
brake.  The  force  of  application  depends  upon  the  current 
and  upon  the  electro-magnets  operating  the  brake  shoes. 
The  attractive  force  of  the  rails  upon  the  magnets  Is  under 
the  control  of  the  motorman  up  to  a  limit  of  150  Ib.  per 
sq.  in.  of  brake  shoe  surface  in  contact  with  the  rails. 


166 

The  strength  of  the  magnet  is  limited  by  the  sectional  area 
of  the  rail,  acting  as  armature,  and  where  the  weight  of  the 
car  makes  a  magnet  of  greater  strength  desirable,  the  track 
shoe  is  divided  into  three  parts,  instead  of  two,  and  wound 
to  form  a  three  pole  magnet,  or  two  electro-magnets  with 
one  common  pole.  With  this  brake  the  diverters  or  resist- 
ances are  arranged  in  two  sets,  one  inside  and  the  other  out- 
side of  the  car.  Those  inside  are  used  to  heat  the  car,  for 
which  the  starting  current  and  braking  current  is  ample. 
The  two  sets  of  diverters  may  be  so  combined  that  any  de- 
sired portion  of  the  heat  generated  may  be  used  in  the  car 
and  the  remainder,  if  any,  passes  into  the  open  air. 

The  friction  of  the  track  brake  shoe  may  also  be  adjusted 
to  some  extent  through  the  angular  inclination  of  the  push 
rods,  c,  by  which  some  of  the  weight  of  the  car  may  be 
thrown  upon  the  track  shoes,  the  levers  d  being  correspond- 
ingly adjusted  to  reduce  the  wheel  brake  shoe  pressure  in 
proportion  as  the  weight  is  transferred  to  the  track  shoe. 
The  current  declines  with  the  speed  during  a  stop,  and  in 
bad  weather,  when  the  condition  of  the  rails  is  liable  to  be 
accompanied  by  wheel  sliding,  the  braking  force  operating 
the  wheel  brake  is  correspondingly  reduced  so  that 
the  force  of  application  of  the  wheel  brakes  is  automat- 
ically proportioned  to  the  rail  friction  which  rotates  the 
wheels.  If  by  chance  the  wheels  should  slide  upon  the  rails, 
the  interruption  of  wheel  rotation  cuts  off  the  track-magnet 
current,  through  which  the  pressure  of  the  brake  shoes  upon 
the  wheel  is  instantly  relaxed  and  rotation  of  the  wheels  is 
resumed,  without  injury  or  serious  loss  of  time. 


CHAPTER  VI. 

ELECTRIC  TRACTION  SYSTEMS. 

We  are  familiar  with  the  trolley  car  running  alone  or 
with  a  trailer,  and  taking  current  from  an  overhead  trolley 
line ;  but  in  addition  to  this  there  are  several  other  methods 
by  which  cars  are  operated  by  electricity.  The  overhead 
trolley  is  probably  the  cheapest  of  any  electrical  system  to 
build,  and  is  easily  maintained  and  operated,  but  beside  this 
there  are  third  rail,  conduit,  surface  contact  and  storage 
battery  systems,  and  systems  using  two  or  more  overhead 
trolley  wires  and  electric  locomotives. 

THIRD  RAIL  SYSTEM. 

The  third  rail  system  is  one  in  which  a  rail  called  the  third 
rail  is  substituted  for  the  overhead  trolley.  The  third  rail 
may  be  placed  either  between  the  two  track  rail  or  outside 
of  them.  The  third  rail  system  is  at  the  present  time  assum- 
ing considerable  importance  in  the  electric  railway  field,  and 
this  type  of  construction  is  required  where  heavy  cars  are 
made  up  into  trains  and  operated  at  high  speed.  The  rea- 
son that  the  third  rail  system  is  preferable  to  the  overhead 
trolley  in  such  cases  is  that  the  weight  and  speed  of  trains 
requires  an  amount  of  current  which  is  too  great  to  be  col- 
lected by  the  overhead  trolley  wheels  owing  to  its  very  lim- 
ited contact.  In  the  third  rail  system  the  sliding  contact  is 
maintained  by  means  of  a  shoe  which  slides  along  the  top  of 
the  third  rail,  and  may  be  given  sufficient  area  to  carry  any 
required  amount  of  current.  The  first  commercial  installa- 


168 

tion  of  the  third  rail  system  was  on  the  intra-mural  railway 
at  the  World's  Fair  in  1893.     It  was  next  adopted  by  the 
elevated  roads  of  Chicago  and  afterwards  on  a  branch  line  of 
the  New  York  &  New  Haven  railroad.    The  system  was  sub- 
sequently extended  to  various  branches  of  the  same  road. 
It  was  next  used  on  the  Albany  &  Hudson  Ry.,  after  which 
it  -was  installed  on  the  Aurora,  Elgin  &  Chicago  Ry.     A 
third  rail  system  in  which  the  third  rail  is  protected  by  a 
wooden  sheathing  on  top  and  at  one  side  has  been  installed 
on  the  Wilkesbarre  &  Hazelton  railroad.     All  the  elevated 
roads  in  Chicago,  Boston  and  New  York  are  now  equipped 
with  the  third  rail  system.    The  third  rail  is  elevated  about 
six  inches  above  the  level  of  the  track  rails  and  is  supported 
on  insulators  resting  on  the  ties.    In  this  country  the  third 
rail  is  always  located  outside  of  the  track  rails,  the  general 
practice  being  in  elevated  railway  work  to  locate  the  third 
rail  20  inches  from  the  track  rail,  and  in  surface  road  work 
27  inches  from  the  track  rail.    In  the  earlier  third  rail  sys- 
tems, insulators  were  made  of  wood,  but  it  has  been  found 
that  after  a  year  or  two  of  service  the  wood  absorbs  suf- 
ficient moisture  to  partly  short  circuit  the  insulator,  and 
cause  considerable   loss   through   leakage.     A   number   of 
these  wooden  insulators  have  been  found  burning  at  various 
times,  and  it  has  been  noticed  that  the  burning  takes  place 
at  the  inside  of  the  insulator  instead  of  at  its  surface,  show- 
ing it  to  be  due  to  capillary  action  of  the  water  lying  upon 
the  ties  and  road  bed.     Aside   from  the  location  of  the 
supply  conductor,  there  is  no  difference  between  the  third 
rail  and  the  overhead  system,  so  far  as  the  circuits  upon  the 
car  are  concerned.   The  current  from  the  third  rail  is  col- 
lected by  means  of  a  shoe  which  slides  along  the  top  of  the 
rail.   The  shoe  is  fastened  to  the  journal  box  or  some  part 
of  the  truck  by  means  of  a  hinged  joint  which  allows  it  to 
bear  on  the  rail  with  a  pressure  equal  to  its  weight.    It  is,  of 


169 

course,  thoroughly  insulated  from  all  metallic  parts  of  the 
car. 

The  third  rail  system  is  applicable  only  to  roads  running 
upon  a  private  right  of  way  and  is  especially  adapted  to  the 
operations  of  cars  in  trains,  which  requires  a  larger  amount 
of  current  than  can  be  collected  by  one  trolley  wheel.  Shoes 
are  placed  at  the  journal  boxes  of  all  the  cars  so  that  on  a 
long  train  the  current  is  collected  at  a  number  of  different 
points.  Where  the  road  crosses  a  highway  the  third  rail 
is  broken,  stopping  at  each  side  of  the  crossing,  and  the  car 
is  allowed  to  drift  over  the  gap  without  current.  The  con- 
tinuity of  the  third  rail  circuit  is  secured  by  attaching  an 
underground  cable  between  the  two  ends  of  the  third  rail, 
and  these  ends  are  built  with  a  downward  curve  so  that  the 
shoes,  which  can  only  drop  slightly  below  their  normal 
position,  do  not  make  violent  contact  with  the  rail,  but  ride 
up  on  the  curved  portion. 

SURFACE  CONTACT  SYSTEMS. 

Surface  contact  systems  are  those  in  which  there  are  no 
exposed  conductors,  and  a  number  of  such  systems  have 
ben  devised  chiefly  to  avoid  the  use  of  overhead  wires  or 
open  underground  conduits.  While  these  systems  vary  con- 
siderably as  to  details  they  all  contain  similar  essential  parts. 
These  are  contact  plates  or  buttons  of  iron  set  at  short  inter- 
vals apart  between  the  tracks,  collector  bars  carried  under 
the  cars  which  make  contact  with  the  buttons,  and  a  feeder 
cable  buried  in  the  ground  which  is  connected  to  each  but- 
ton by  means  of  a  magnetic  switch.  Normally  there  is  no 
current  in  the  buttons  and  they  are  "dead"  except  when  a 
car  is  directly  over  them,  but  when  the  collector  bar  comes 
in  contact  with  a  button  it  is  magnetized  and  this  magnetism 
closes  the  magnetic  switch  and  completes  the  circuit  from 
the  underground  conductor  through  the  button  thence  to 


170 

the  collector  bar  and  to  the  car  circuits.  The  buttons  are 
placed  close  enough  together  so  that  before  the  collector  bar 
has  left  one  button  it  makes  connection  with  the  next  one. 
Sometimes  two  rows  of  buttons  are  used  and  two  bars  under 
the  car,  one  for  magnetizing  the  switches  and  the  other 
for  collecting  the  current.  The  current  for  magnetizing  the 
bar  and  buttons  may  be  obtained  from  a  few  cells  of  storage 
battery  carried  on  the  car.  This  system  is  used  to  a  con- 
siderable extent  in  Paris,  France,  and  has  just  been  applied 
to  eleven  miles  of  track  in  Wolverhampton,  England,  but  has 
not  been  used  in  this  country  except  on  a  small  scale  in  yards 
and  about  manufacturing  establishments.  It  is  less  reliable 
than  the  trolley  system  owing  to  the  use  of  so  many  under- 
ground magnetic  switches  which  are  liable  to  get  out  of 
order  and  fail  to  open,  thus  leaving  "live"  contact  buttons  in 
the  streets. 

CONDUIT  SYSTEM. 

The  conduit  system  is  one  in  which  the  conductors  are  car- 
ried in  a  conduit  under  the  surface  of  the  street  similar  to  a 
cable  railway  conduit.  Unlike  the  other  system  described 
the  conduit  system  does  not  make  use  of  the  tracks  for  a 
return  circuit,  but  instead,  both  the  positive  and  negative 
conductors  are  supported  on  insulators  fastened  inside  of 
the  conduit.  The  current  is  taken  from  these  conductors  by 
means  of  a  trolley  extending  down  through  a  slot  in  the  sur- 
face of  the  road.  This  underground  trolley  is  called  a  plow. 
The  conductors  are  generally  composed  of  copper  bars  and 
the  plow  contains  sliding  contact  pieces  which  rest  on  these 
bars.  One  side  of  the  plow  collects  the  current,  which  is  led 
to  the  controllers  and  motors,  after  which  it  passes  again  to 
the  plow  contact  which  is  in  connection  with  the  return 
circuit. 

This  system  is  in  use  in  New  York  City  and  Washington, 
D.  C.,  and  in  a  few  European  cities  where  overhead  conduc- 


171 

tors  are  prohibited.    It  is  very  expensive  to  build,  costing  in 
the  neighborhood  of  $100,000  per  mile. 

STORAGE  BATTERY  CARS. 

A  storage  battery  car  is  one  which  has  electric  current 
stored  in  cells  or  batteries  in  the  car,  which  supply  current 
to  the  car  motor.  Such  a  car  can  run  on  any  railroad  track 
and  requires  no  wires  or  conductors  outside  of  itself.  The 
storage  cell  consists  of  plates  of  lead  immersed  in  acid,  and 
these  cells  are  charged  at  the  power  station  by  putting  them 
in  circuit  with  a  dynamo,  the  electric  current  causing  chem- 
ical changes  in  the  lead.  These  changes  represent  a  certain 
amount  of  electrical  energy,  which  is  given  out  when  the 
batteries  are  connected  to  the  car  motors.  The  battery 
merely  supplies  current  for  the  car  and  the  controllers  are 
similar  to  those  on  trolley  cars  and  the  method  of  operation 
is  the  same.  Storage  battery  cars  are  not  very  extensively 
used,  as  the  cost  of  operation  is  considerably  higher  than 
that  of  trolley  cars.  This  is  chiefly  due  to  the  batteries, 
which  are  expensive  to  install  and  which  wear  out  rapidly 
under  the  severe  conditions  of  street  railway  work. 

ELECTRIC  LOCOMOTIVES. 

For  the  purpose  of  moving  long  trains  of  cars,  switching 
freight  cars  and  other  purposes  where  the  power  required  is 
so  great  that  the  motors  cannot  be  mounted  on  the  trucks 
of  ordinary  cars,  electric  locomotives  are  used  and  current 
is  taken  from  an  overhead  wire  or  a  third  rail,  as  with  a 
trolley  car.  These  locomotives  are  equipped  with  motors  of 
large  capacity  and  their  frames  are  very  heavy  so  as  to  se- 
cure sufficient  adhesion  to  the  track  to  pull  very  heavy  loads. 
The  controllers  and  other  apparatus  on  electric  locomotives 
are  similar  to  those  on  cars  of  ordinary  size,  being  merely 
larger  and  heavier  to  accommodate  the  larger  current  used. 


GLOSSARY. 

Ampere — The  standard  unit  of  electric  current   which   is 
equivalent  to  the  current  flowing  through  a  circuit  hav- 
ing one  ohm  resistance  with  a  pressure  of  one  volt. 
Volts 

Current= 

resistance. 

Armature — The  part  of  a  motor  or  dynamo  which  revolves 
and  produces  power  or  generates  current. 

Brushes — On  railway  generators  and  motors  they  are  blocks 
of  carbon  held  in  brass  holders  with  light  springs  to 
press  them  against  the  commutator,  and  through  which 
the  current  passes  to  or  from  the  commutator  and  arma- 
ture, or  from  the  stationary  conductor  of  the  circuit  to 
the  rotary  conductors  or  vice  versa. 

Brush  Holders — Devices  to  hold  the  brushes ;  they  are 
adjustable  so  that  the  brushes  can  be  lifted  to  prevent 
sparking. 

Circuit  Breaker — An  automatic  switch  arranged  to  open 
whenever  the  current  becomes  greater  than  a  certain 
amount  and  endangers  the  machine.  It  consists  of  a  few 
turns  of  wire  around  an  iron  core  which  becomes  a 
magnet  of  greater  and  greater  power  as  the  current  in- 
creases until  it  throws  open  the  switch  or  releases  a 
catch  which  allows  a  spring  to  open  the  switch. 

Commutator — A  set  of  copper  segments  separated  by  thin 
strips  of  mica  insulation  in  the  form  of  a  drum ;  through 
the  segments  covered  by  the  positive  brushes  the  posi- 
tive current  passes  to  the  armature  in  a  motor  and  from 
it  in  a  dynamo. 

Compound  Winding — The  field  magnets  of  a  railway  dytta- 


173 

mo  always  have  two  windings,  through  one  of  which, 
the  "series,"  the  main  current  passes,  and  through  the 
other,  the  "shunt,"  a  branch  of  the  main  current  passes. 

Conductors — The  part  of  the  dynamo,  motor  or  line,  or  cir- 
cuit through  which  the  current  flows. 

Diverter — A  rheostat  or  resistance  placed  in  circuit  with  a 
motor  to  reduce  the  current. 

Electro-Magnet — An  iron  or  steel  core  around  which  a 
spool  of  wire  is  placed  to  carry  current. 

Electro-Motive  Force — The  voltage  or  volts'  pressure  in  a 
circuit;  e.  g.,  the  trolley  circuit  has  an  electro-motive 
force  of  500  volts.  The  abbreviation  is  e.  m.  f. 

Field — The  part  of  a  motor  or  dynamo  which  contains  the 
magnets. 

Fuse — A  strip  of  metal,  generally  some  alloy  of  lead,  which 
easily  melts  when  too  great  a  current  is  flowing  in  the 
circuit.  It  is  mounted  usually  on  a  piece  of  porcelain 
called  a  fuse  block. 

Generator — Has  the  same  meaning  as  dynamo,  but  is  com- 
monly used  to  denote  the  large  machines  in  the  station. 

Horse  Power — The  standard  rate  of  work  being  33,000  foot- 
pounds per  minute.  If  a  machine  can  lift  1,000  pounds 
33  feet  in  one  minute  its  capacity  is  one-horse  power. 
The  abbreviation  is  h.  p.  Electrical  equivalent,  h.  p.= 
746  watts. 

Insulation — A  non-conductor,  as  air,  rubber,  mica,  varnish, 
etc.,  through  which  electricity  does  not  readily  pass. 

Lightning  Arresters — They  are  devices  which  offer  a  by- 
pass to  lightning  to  prevent  damage  to  machines  when 
the  line  is  carrying  a  discharge  of  lightning  by  conduct- 
ing it  to  the  earth. 

Magnetic  Blow-Out — When  switches  are  opened  or  the  cur- 
rent shut  off  in  controllers  an  arc  is  formed,  or  the  cur- 
rent passing  through  the  air  from  one  conductor  to  the 


174 

other.   A  magnet  is  placed  near  the  point  where  the  arc 
is  formed  and  draws  it  aside  and  blows  it  out. 
Ohm  —  The  standard  of  electrical  resistance  through  which 
one  ampere  of  current  will  flow  with  a  pressure  of  one 
volt. 

volts 


current 

Parallel  or  Multiple  Connection  —  A  circuit  in  which  the  cur- 
rent divides  and  part  passes  through  each  motor,  dyna- 
mo or  other  electrical  device. 

Poles  or  Pole  Pieces  —  The  core  ends  which  project  on  the 
fields  and  conform  to  the  shape  of  the  armature,  and 
geerally  carry  the  field  windings. 

Resistance  —  An  obstruction  to  the  flow  of  current.  All  sub- 
stances have  some  resistance,  but  resistance  boxes  or 
rheostats  have  iron  wire  or  sometimes  carbon  strips 
for  the  circuit.  Resistance  produces  heat  in  the  circuit, 
and  by  this  means  the  current  in  passing  through  an 
electric  car  heater  makes  the  wires  very  hot. 

Series  Connection  —  When  the  current  passes  through  one 
motor,  dynamo  or  electrical  device  and  thereafter  into 
one  or  more  devices. 

Sparking  —  The  flashing  of  the  current  which  occurs  at  the 
commutator  when  there  is  poor  contact,  the  brushes  are 
in  bad  order,  the  commutator  is  dirty,  or  the  dynamo 
or  motor  is  carrying  too  heavy  a  load. 

Volt  —  The  standard  of  electrical  pressure,  or  the  pressure  to 
force  one  ampere  of  current  through  one  ohm  resist- 
ance. Volts=amperes  x  ohms. 

Watt  —  The  rate  of  performance  of  work  measured  electric- 
ally; the  capacity  of  a  dynamo  or  motor  is  measured 
in  watts  and  is  the  product  of  volts  by  amperes.  A 
kilowatt  is  1,000  watts  and  is  equal  to  1.34  h.  p. 


INDEX. 

Accidents,  precautions  against  41 

Ampere 28 

Armature   14 

Armature  core    76 

Arrester,  Lightning 25,  53,  87 

Carton  89 

General   Electric    .-••.. •  •  •  • 91 

Wurtz   non-arcing    90 

Blow-out,  magnetic .83,    104 

Brakes    •  • .   13 

Air    142 

Brill    , 150 

Christensen    .  .- ..155 

Construction    of    141 

Electric    •  • 142,    160 

Hand    141 

Magann ....... •  • 162 

McGuire    147 

Momentum .141 

Murray  anti-friction    162 

Operation   of    46 

Price    151 

Standard   Air  Brake  Co 153 

Sterling 149 

Taylor    145 

Track 142 

Westinghouse  magnetic  track    164 

Brush  holder 52 

Choke   coil    91 

Circuit   breaker    25 

Automatic    86 

I.  T.   E. < 87 

Coil,   grounded    53 

Commutator 74,   77 

Flashing    of    57 

Conductors,   electrical 26 

Conduit    system 170 

Contactors   136 

Contact,    rail 51 


176 

Controllers,    contact    fingers 52 

Description   of    •  • . 92 

General  Electric    104 

Master •  • 134 

Operation    of    34 

Running  points    ••..••...... 35 

Series   parallel    103 

Steel   Motor   Co 130 

Type  B 103,   105,  117 

Type    C  6    134 

Type   D 101 

Type    K. . . 103,    104,    105 

Type  L 103,  104,   115 

Type  R  104,  105,   1 13 

Walker 126 

Westinghouse 118 

Control,  type  M 134 

Diverter    94 

Dynamo 71 

Edison    74 

Economy  of  current   . •  •  34 

Electro-magnet   72 

Emergencies 37 

Fuse 25 

Blowing  of -.-So,  S3 

Box    84 

D.  E.  W 85 

General    Electric    85 

Noark 85 

Westinghouse    85 

Gear,   split 14 

Grounds 58 

Heating  of  motors   55 

Insulators 26 

Kicking   coil    89 

Lines  of  Force 65 

Locomotives,    electric    171 

Magnet    ." 63 

Magnets,  field 14,  17 

Motor 14 

Box  frame ..  21 


177 

Parts   of    81 

Principles  of 63 

Railway 76 

Multiple  connection 97 

Field . 75 

Unit  Control,  General   Electric 133 

Westinghouse     137 

Needle,  magnetic    •  •  68 

Ohm's    La  \v     28 

Overhead  material 29 

Parallel  connection 96 

Power,   saving  of- 39 

Transmitting    26 

Rail,  dead 51 

Reversing 38 

Rheostat    .............. .\ 39 

Burnt 53 

Thomson-Houston .92 

Sand    box 41 

Series  connection 96 

-parallel   connection    98 

Short   circuit    53,    57 

Skidding    .......................... 47 

Stop,    emergency    37 

Storage  battery  cars 171 

Surface  contact  systems    169 

Suspension,   Motor 18 

Switchboard    31 

Switch,   canopy .......... . 24,  83 

Gut-out ..104 

Multiple   control 138 

Third    rail    system 167 

Transmission,   electrical 31 

Trolley    base    23 

Troubles,  How  to  remedy    49 

Trucks 12 

Volt .....28 

Wheel,   flat    . 57 

Slip    41 

Wiring,    car    21 


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